eliminate 404 errs that eventually lead to non-functional server

This restores https://github.com/xtuple/xtuple-server-core/pull/488/files#diff-3af436e6760a0c5f1e3d16a3384853a8L17
That missing line lead to 404 errors during subsequent `apt-get`s. In my testing that eventually resulted in web app login failures.