Changes

redmine: fix auto-scan of repositories

While inspecting the running docker container I found that the script
already runs as redmine user. I had assumed that it runs as root
earlier. Running 'su' as redmine user fails, therefore it currently does
not run the fetch_changesets command.

Related: OS#6083
Change-Id: I195311b93868eb5fd73ad6e3c165d48f3b7b53ce