Revert "Disable pre-signed S3 URLs for default storage"
Revert "Disable pre-signed S3 URLs for default storage"

Turns out this breaks images altogether on prod & stage. Revert for now
while we figure out how to do this properly.

This reverts commit 033999d7d0a021c50884f0b8f3a7b275eb77dc7d.

clouserw/testpilot,meandavejustice/testpilot,chuckharmston/testpilot,lmorchard/testpilot,lmorchard/idea-town,fzzzy/testpilot,lmorchard/idea-town-server,lmorchard/idea-town,dannycoates/testpilot,mozilla/idea-town-server,chuckharmston/testpilot,lmorchard/idea-town-server,clouserw/testpilot,mathjazz/testpilot,flodolo/testpilot,flodolo/testpilot,dannycoates/testpilot,6a68/idea-town,chuckharmston/testpilot,lmorchard/testpilot,lmorchard/idea-town-server,mozilla/idea-town-server,mozilla/testpilot,6a68/testpilot,mozilla/idea-town,mathjazz/testpilot,6a68/idea-town,lmorchard/idea-town,flodolo/testpilot,ckprice/testpilot,mathjazz/testpilot,flodolo/testpilot,lmorchard/testpilot,lmorchard/idea-town-server,mozilla/testpilot,fzzzy/testpilot,6a68/testpilot,lmorchard/testpilot,mozilla/testpilot,fzzzy/testpilot,clouserw/testpilot,ckprice/testpilot,6a68/testpilot,dannycoates/testpilot,mathjazz/testpilot,chuckharmston/testpilot,6a68/testpilot,mozilla/testpilot,mozilla/idea-town,6a68/idea-town,mozilla/idea-town-server,ckprice/testpilot,dannycoates/testpilot,lmorchard/idea-town,mozilla/idea-town,mozilla/idea-town,meandavejustice/testpilot,6a68/idea-town,fzzzy/testpilot,meandavejustice/testpilot,mozilla/idea-town-server,clouserw/testpilot,meandavejustice/testpilot,ckprice/testpilot