Update Heroku-guide.md
Update Heroku-guide.md

Removing some of the confusion around what format S3 bucket names and regions should be entered as well as providing an example of an S3 policy that follows best security practices for this sort of thing.
pointlessone/mastodon,thnkrs/mastodon,masto-donte-com-br/mastodon,lindwurm/mastodon,res-ac/mstdn.res.ac,koteitan/googoldon,kirakiratter/mastodon,kagucho/mastodon,clworld/mastodon,masto-donte-com-br/mastodon,mosaxiv/mastodon,moeism/mastodon,thnkrs/mastodon,theoria24/mastodon,koba-lab/mastodon,lynlynlynx/mastodon,havicon/mastodon,palon7/mastodon,cobodo/mastodon,danhunsaker/mastodon,ykzts/mastodon,ykzts/mastodon,hugogameiro/mastodon,tootsuite/mastodon,unarist/mastodon,lynlynlynx/mastodon,koba-lab/mastodon,ambition-vietnam/mastodon,NS-Kazuki/mastodon,Ryanaka/mastodon,TheInventrix/mastodon,rutan/mastodon,narabo/mastodon,corzntin/mastodon,maa123/mastodon,tootcafe/mastodon,ikuradon/mastodon,cybrespace/mastodon,cobodo/mastodon,salvadorpla/mastodon,tootsuite/mastodon,MastodonCloud/mastodon,imas/mastodon,h3zjp/mastodon,haleyashleypraesent/ProjectPrionosuchus,rutan/mastodon,pso2club/mastodon,YuyaYokosuka/mastodon_animeclub,ms2sato/mastodon,pso2club/mastodon,mecab/mastodon,foozmeat/mastodon,havicon/mastodon,koba-lab/mastodon,Toootim/mastodon,pfm-eyesightjp/mastodon,Ryanaka/mastodon,vahnj/mastodon,gol-cha/mastodon,d6rkaiz/mastodon,im-in-space/mastodon,Toootim/mastodon,imomix/mastodon,tootcafe/mastodon,tootsuite/mastodon,rekif/mastodon,5thfloor/ichiji-social,developer-mstdn18/mstdn18,vahnj/mastodon,honpya/taketodon,haleyashleypraesent/ProjectPrionosuchus,Nyoho/mastodon,KnzkDev/mastodon,hyuki0000/mastodon,blackle/mastodon,MitarashiDango/mastodon,RobertRence/Mastodon,pointlessone/mastodon,mhffdq/mastodon,narabo/mastodon,codl/mastodon,Craftodon/Craftodon,robotstart/mastodon,WitchesTown/mastodon,dissolve/mastodon,palon7/mastodon,TheInventrix/mastodon,unarist/mastodon,unarist/mastodon,vahnj/mastodon,h3zjp/mastodon,Chronister/mastodon,rutan/mastodon,esetomo/mastodon,tcitworld/mastodon,yukimochi/mastodon,mstdn-jp/mastodon,riku6460/chikuwagoddon,nonoz/mastodon,tootcafe/mastodon,Kirishima21/mastodon,d6rkaiz/mastodon,h-izumi/mastodon,kirakiratter/mastodon,RobertRence/Mastodon,nonoz/mastodon,lindwurm/mastodon,ashfurrow/mastodon,danhunsaker/mastodon,MitarashiDango/mastodon,koba-lab/mastodon,foozmeat/mastodon,3846masa/mastodon,res-ac/mstdn.res.ac,abcang/mastodon,ebihara99999/mastodon,sinsoku/mastodon,nonoz/mastodon,h3zjp/mastodon,rainyday/mastodon,robotstart/mastodon,masarakki/mastodon,SerCom-KC/mastodon,saggel/mastodon,masto-donte-com-br/mastodon,SerCom-KC/mastodon,8796n/mastodon,Chronister/mastodon,Monappy/mastodon,pso2club/mastodon,Ryanaka/mastodon,codl/mastodon,increments/mastodon,mecab/mastodon,salvadorpla/mastodon,alarky/mastodon,dunn/mastodon,dissolve/mastodon,heropunch/mastodon-ce,blackle/mastodon,pinfort/mastodon,narabo/mastodon,glitch-soc/mastodon,MitarashiDango/mastodon,pfm-eyesightjp/mastodon,TheInventrix/mastodon,tateisu/mastodon,cybrespace/mastodon,moeism/mastodon,Arukas/mastodon,imomix/mastodon,ykzts/mastodon,3846masa/mastodon,tateisu/mastodon,alarky/mastodon,masarakki/mastodon,narabo/mastodon,primenumber/mastodon,bureaucracy/mastodon,pointlessone/mastodon,kazh98/social.arnip.org,thor-the-norseman/mastodon,honpya/taketodon,palon7/mastodon,WitchesTown/mastodon,tcitworld/mastodon,d6rkaiz/mastodon,mimumemo/mastodon,corzntin/mastodon,danhunsaker/mastodon,amazedkoumei/mastodon,lindwurm/mastodon,yi0713/mastodon,increments/mastodon,moeism/mastodon,sinsoku/mastodon,Nyoho/mastodon,koteitan/googoldon,masto-donte-com-br/mastodon,KnzkDev/mastodon,h-izumi/mastodon,KnzkDev/mastodon,sylph-sin-tyaku/mastodon,primenumber/mastodon,yukimochi/mastodon,kagucho/mastodon,anon5r/mastonon,nonoz/mastodon,jukper/mastodon,PlantsNetwork/mastodon,MastodonCloud/mastodon,kirakiratter/mastodon,saggel/mastodon,HogeTatu/mastodon,clworld/mastodon,imomix/mastodon,mimumemo/mastodon,glitch-soc/mastodon,yukimochi/mastodon,h-izumi/mastodon,infinimatix/infinimatix.net,mosaxiv/mastodon,RobertRence/Mastodon,increments/mastodon,ambition-vietnam/mastodon,sylph-sin-tyaku/mastodon,dissolve/mastodon,Chronister/mastodon,dunn/mastodon,mhffdq/mastodon,rekif/mastodon,cobodo/mastodon,3846masa/mastodon,ms2sato/mastodon,musashino205/mastodon,cobodo/mastodon,salvadorpla/mastodon,kazh98/social.arnip.org,pinfort/mastodon,cybrespace/mastodon,abcang/mastodon,ebihara99999/mastodon,masarakki/mastodon,robotstart/mastodon,3846masa/mastodon,mecab/mastodon,thor-the-norseman/mastodon,masarakki/mastodon,ebihara99999/mastodon,sinsoku/mastodon,8796n/mastodon,ashfurrow/mastodon,YuyaYokosuka/mastodon_animeclub,hyuki0000/mastodon,Kyon0000/mastodon,glitch-soc/mastodon,bureaucracy/mastodon,ikuradon/mastodon,infinimatix/infinimatix.net,theoria24/mastodon,TootCat/mastodon,clworld/mastodon,KnzkDev/mastodon,sylph-sin-tyaku/mastodon,pso2club/mastodon,Monappy/mastodon,mosaxiv/mastodon,pixiv/mastodon,heropunch/mastodon-ce,mosaxiv/mastodon,ms2sato/mastodon,haleyashleypraesent/ProjectPrionosuchus,maa123/mastodon,TootCat/mastodon,salvadorpla/mastodon,kagucho/mastodon,musashino205/mastodon,riku6460/chikuwagoddon,pixiv/mastodon,Monappy/mastodon,yi0713/mastodon,dunn/mastodon,mimumemo/mastodon,corzntin/mastodon,esetomo/mastodon,verniy6462/mastodon,Gargron/mastodon,sylph-sin-tyaku/mastodon,ambition-vietnam/mastodon,anon5r/mastonon,SerCom-KC/mastodon,abcang/mastodon,Ryanaka/mastodon,HogeTatu/mastodon,amazedkoumei/mastodon,developer-mstdn18/mstdn18,YuyaYokosuka/mastodon_animeclub,blackle/mastodon,mstdn-jp/mastodon,Craftodon/Craftodon,Nyoho/mastodon,vahnj/mastodon,developer-mstdn18/mstdn18,NS-Kazuki/mastodon,rutan/mastodon,imas/mastodon,tcitworld/mastodon,kazh98/social.arnip.org,MitarashiDango/mastodon,hyuki0000/mastodon,Monappy/mastodon,jukper/mastodon,havicon/mastodon,danhunsaker/mastodon,Nyoho/mastodon,RobertRence/Mastodon,dunn/mastodon,dwango/mastodon,tri-star/mastodon,NS-Kazuki/mastodon,amazedkoumei/mastodon,ykzts/mastodon,5thfloor/ichiji-social,WitchesTown/mastodon,ikuradon/mastodon,5thfloor/ichiji-social,kagucho/mastodon,im-in-space/mastodon,librize/mastodon,PlantsNetwork/mastodon,kirakiratter/mastodon,lynlynlynx/mastodon,Chronister/mastodon,tootsuite/mastodon,pixiv/mastodon,TootCat/mastodon,imas/mastodon,tri-star/mastodon,hugogameiro/mastodon,haleyashleypraesent/ProjectPrionosuchus,8796n/mastodon,mimumemo/mastodon,cybrespace/mastodon,gol-cha/mastodon,res-ac/mstdn.res.ac,dwango/mastodon,heropunch/mastodon-ce,Gargron/mastodon,codl/mastodon,foozmeat/mastodon,yi0713/mastodon,WitchesTown/mastodon,rainyday/mastodon,mstdn-jp/mastodon,maa123/mastodon,verniy6462/mastodon,palon7/mastodon,dwango/mastodon,ashfurrow/mastodon,PlantsNetwork/mastodon,im-in-space/mastodon,theoria24/mastodon,pinfort/mastodon,imas/mastodon,Kirishima21/mastodon,primenumber/mastodon,gol-cha/mastodon,dwango/mastodon,glitch-soc/mastodon,vahnj/mastodon,Kirishima21/mastodon,honpya/taketodon,res-ac/mstdn.res.ac,unarist/mastodon,bureaucracy/mastodon,TheInventrix/mastodon,verniy6462/mastodon,rainyday/mastodon,koteitan/googoldon,pointlessone/mastodon,jukper/mastodon,imomix/mastodon,increments/mastodon,lynlynlynx/mastodon,summoners-riftodon/mastodon,Kirishima21/mastodon,HogeTatu/mastodon,tri-star/mastodon,Toootim/mastodon,summoners-riftodon/mastodon,riku6460/chikuwagoddon,summoners-riftodon/mastodon,tateisu/mastodon,corzntin/mastodon,honpya/taketodon,MastodonCloud/mastodon,ashfurrow/mastodon,amazedkoumei/mastodon,pfm-eyesightjp/mastodon,pfm-eyesightjp/mastodon,mhffdq/mastodon,yi0713/mastodon,Arukas/mastodon,h-izumi/mastodon,Kyon0000/mastodon,primenumber/mastodon,lindwurm/mastodon,NS-Kazuki/mastodon,PlantsNetwork/mastodon,tateisu/mastodon,kazh98/social.arnip.org,verniy6462/mastodon,foozmeat/mastodon,hugogameiro/mastodon,Kyon0000/mastodon,gol-cha/mastodon,musashino205/mastodon,SerCom-KC/mastodon,rainyday/mastodon,anon5r/mastonon,TootCat/mastodon,clworld/mastodon,librize/mastodon,riku6460/chikuwagoddon,tri-star/mastodon,h3zjp/mastodon,saggel/mastodon,codl/mastodon,im-in-space/mastodon,mhffdq/mastodon,ebihara99999/mastodon,mecab/mastodon,Gargron/mastodon,TheInventrix/mastodon,esetomo/mastodon,thnkrs/mastodon,hyuki0000/mastodon,koteitan/googoldon,tootcafe/mastodon,Craftodon/Craftodon,rekif/mastodon,thor-the-norseman/mastodon,Arukas/mastodon,mstdn-jp/mastodon,abcang/mastodon,pixiv/mastodon,yukimochi/mastodon,musashino205/mastodon,ambition-vietnam/mastodon,rekif/mastodon,MastodonCloud/mastodon,theoria24/mastodon,blackle/mastodon,alarky/mastodon,summoners-riftodon/mastodon,librize/mastodon,YuyaYokosuka/mastodon_animeclub,Arukas/mastodon,alarky/mastodon,ikuradon/mastodon,5thfloor/ichiji-social,Craftodon/Craftodon,anon5r/mastonon,esetomo/mastodon,maa123/mastodon,pinfort/mastodon,d6rkaiz/mastodon,infinimatix/infinimatix.net,hugogameiro/mastodon,Toootim/mastodon