delete_mirror.sh should not delete the project with the same name in another group

[Adol1111]

I have two project with the same name, but in different group. When I run "delete_mirror.sh --delete xxxx", the project which in another group not Mirror group is deleted.

I see when you run delete_mirror.sh script, you only find project by project name without group name.

https://github.com/samrocketman/gitlab-mirrors/blob/75483cd906e0588200a7dcf4e1ff555e190b965a/lib/manage_gitlab_project.py#L154