Revert "Autologin: Test logged session against remote user"

This reverts commit 64954e99244f26cc6b6dccc7d60a253c105bd550.

If the strip_username_regex is configured on the autologin backend and applies on a user's name,
the authenticated user's username does never match the REMOTE_USER server variable.
Thus the application will logout/login on every request which results in a redirect loop.

refs #6462