While checking the 4.3.0 rc0, I noticed that there's a release directory in the 4.0 branch in git, and this release directory contains a dir structure with what seems to be a full source tarball of Phoenix (added in commit 4d085f4b5399a538e10fe8d9f43b15cca7ccc3b3)
I assume that this was an accident and needs to be removed, but there might be something in a release script that needs to be tweaked to avoid this happening again in the future as well. - Gabriel