docs: Fix missing wget when downloading tsearch_extra.
docs: Fix missing wget when downloading tsearch_extra.

Fixes #3509.

JPJPJPOPOP/zulip,dhcrzf/zulip,synicalsyntax/zulip,tommyip/zulip,jainayush975/zulip,vabs22/zulip,aakash-cr7/zulip,jainayush975/zulip,samatdav/zulip,andersk/zulip,j831/zulip,dhcrzf/zulip,zulip/zulip,sharmaeklavya2/zulip,dattatreya303/zulip,ryanbackman/zulip,eeshangarg/zulip,JPJPJPOPOP/zulip,jphilipsen05/zulip,punchagan/zulip,dawran6/zulip,susansls/zulip,vaidap/zulip,samatdav/zulip,aakash-cr7/zulip,jphilipsen05/zulip,blaze225/zulip,dattatreya303/zulip,brainwane/zulip,zulip/zulip,andersk/zulip,hackerkid/zulip,j831/zulip,susansls/zulip,Galexrt/zulip,j831/zulip,showell/zulip,jphilipsen05/zulip,synicalsyntax/zulip,jainayush975/zulip,punchagan/zulip,christi3k/zulip,christi3k/zulip,dawran6/zulip,JPJPJPOPOP/zulip,rishig/zulip,aakash-cr7/zulip,amanharitsh123/zulip,verma-varsha/zulip,hackerkid/zulip,blaze225/zulip,kou/zulip,hackerkid/zulip,amanharitsh123/zulip,kou/zulip,dawran6/zulip,tommyip/zulip,Galexrt/zulip,punchagan/zulip,synicalsyntax/zulip,mahim97/zulip,eeshangarg/zulip,jrowan/zulip,PhilSk/zulip,jainayush975/zulip,samatdav/zulip,brockwhittaker/zulip,vaidap/zulip,timabbott/zulip,Galexrt/zulip,Galexrt/zulip,samatdav/zulip,JPJPJPOPOP/zulip,andersk/zulip,souravbadami/zulip,eeshangarg/zulip,timabbott/zulip,j831/zulip,kou/zulip,andersk/zulip,showell/zulip,rht/zulip,shubhamdhama/zulip,brockwhittaker/zulip,punchagan/zulip,dattatreya303/zulip,sonali0901/zulip,jackrzhang/zulip,ryanbackman/zulip,mahim97/zulip,showell/zulip,rht/zulip,zulip/zulip,sonali0901/zulip,JPJPJPOPOP/zulip,jphilipsen05/zulip,blaze225/zulip,susansls/zulip,jrowan/zulip,brockwhittaker/zulip,brockwhittaker/zulip,punchagan/zulip,jrowan/zulip,synicalsyntax/zulip,showell/zulip,jackrzhang/zulip,hackerkid/zulip,brockwhittaker/zulip,SmartPeople/zulip,jackrzhang/zulip,Galexrt/zulip,dattatreya303/zulip,rishig/zulip,blaze225/zulip,synicalsyntax/zulip,shubhamdhama/zulip,dawran6/zulip,tommyip/zulip,sharmaeklavya2/zulip,mahim97/zulip,hackerkid/zulip,hackerkid/zulip,shubhamdhama/zulip,shubhamdhama/zulip,timabbott/zulip,susansls/zulip,PhilSk/zulip,rht/zulip,tommyip/zulip,ryanbackman/zulip,susansls/zulip,rht/zulip,dawran6/zulip,zulip/zulip,jphilipsen05/zulip,vaidap/zulip,vabs22/zulip,souravbadami/zulip,sharmaeklavya2/zulip,rishig/zulip,showell/zulip,souravbadami/zulip,amanharitsh123/zulip,rishig/zulip,dhcrzf/zulip,kou/zulip,timabbott/zulip,amanharitsh123/zulip,PhilSk/zulip,brainwane/zulip,aakash-cr7/zulip,timabbott/zulip,dhcrzf/zulip,timabbott/zulip,sonali0901/zulip,vabs22/zulip,synicalsyntax/zulip,ryanbackman/zulip,blaze225/zulip,verma-varsha/zulip,tommyip/zulip,brainwane/zulip,dawran6/zulip,sonali0901/zulip,tommyip/zulip,sharmaeklavya2/zulip,jackrzhang/zulip,jphilipsen05/zulip,eeshangarg/zulip,shubhamdhama/zulip,dhcrzf/zulip,blaze225/zulip,jackrzhang/zulip,shubhamdhama/zulip,kou/zulip,christi3k/zulip,dattatreya303/zulip,rht/zulip,kou/zulip,eeshangarg/zulip,sonali0901/zulip,PhilSk/zulip,ryanbackman/zulip,brainwane/zulip,j831/zulip,rishig/zulip,aakash-cr7/zulip,jackrzhang/zulip,aakash-cr7/zulip,Galexrt/zulip,shubhamdhama/zulip,SmartPeople/zulip,vabs22/zulip,andersk/zulip,verma-varsha/zulip,amanharitsh123/zulip,verma-varsha/zulip,christi3k/zulip,eeshangarg/zulip,j831/zulip,synicalsyntax/zulip,souravbadami/zulip,christi3k/zulip,jrowan/zulip,vabs22/zulip,zulip/zulip,samatdav/zulip,dhcrzf/zulip,SmartPeople/zulip,showell/zulip,souravbadami/zulip,rht/zulip,vaidap/zulip,rishig/zulip,zulip/zulip,amanharitsh123/zulip,brainwane/zulip,souravbadami/zulip,ryanbackman/zulip,punchagan/zulip,brainwane/zulip,JPJPJPOPOP/zulip,rishig/zulip,eeshangarg/zulip,zulip/zulip,sonali0901/zulip,punchagan/zulip,jainayush975/zulip,mahim97/zulip,sharmaeklavya2/zulip,jrowan/zulip,sharmaeklavya2/zulip,SmartPeople/zulip,verma-varsha/zulip,brockwhittaker/zulip,jainayush975/zulip,SmartPeople/zulip,susansls/zulip,Galexrt/zulip,mahim97/zulip,PhilSk/zulip,jackrzhang/zulip,tommyip/zulip,kou/zulip,andersk/zulip,mahim97/zulip,vaidap/zulip,PhilSk/zulip,christi3k/zulip,vaidap/zulip,andersk/zulip,brainwane/zulip,samatdav/zulip,SmartPeople/zulip,dhcrzf/zulip,jrowan/zulip,vabs22/zulip,hackerkid/zulip,showell/zulip,rht/zulip,timabbott/zulip,verma-varsha/zulip,dattatreya303/zulip