Allow contributions from GitLab private e-mail

When I made !155 (closed) and !156 I noticed that CI does not like using the GitLab private e-mail. It looks like that was intentional: https://gitlab.freedesktop.org/freedesktop/ci-templates/-/blob/master/tools/ci_fairy.py#L193 . In my opinion contributions from a GitLab private e-mail should be allowed, so that you do not have to publicly share your real e-mail. I also think that a GitLab user would still be enough to identify who made it and it is also still possible to contact the person on GitLab by mentioning that username.