Update installation.md
Update installation.md

Replaced old text with updated text: "Set up the infrastructure after the Appliance Project Manager has shared the required AMI file with you"

jeffreylees/docs,yvonnewilson/docs,yvonnewilson/docs,auth0/docs,auth0/docs,auth0/docs,yvonnewilson/docs,jeffreylees/docs,jeffreylees/docs