bugfix: move rc->output->set_env inside if that checks if user is logged in
bugfix: move rc->output->set_env inside if that checks if user is logged in

Reason:
Without that, bin/updatecss.sh fails silently

teonsystems/roundcube-plugin-keyboard-shortcuts-ng,teonsystems/roundcube-plugin-keyboard-shortcuts-ng,teonsystems/roundcube-plugin-keyboard-shortcuts-ng