Git trace logging is always on
The git trace logging file is somewhat hardcoded: https://gitlab.com/gitlab-org/omnibus-gitlab/blob/master/files/gitlab-cookbooks/gitlab/recipes/gitlab-shell.rb#L109
And gitlab-shell turns git trace logging on as soon as the file location is provided. This has resulted in massive logs in production, and no convinient way to turn it off.
We should make the log directory configurable, and default it to nil.