git-repo: "playground-status" cannot check for some issues currently

[jku]

the design currently expects the GH action to call PlaygroundRepository.status(rolename) for each modified role:
this is useful but not sufficient.

Some cases this does not cover (there are probably more):

• removed delegated roles
• target files in targets/ changing without the metadata changing EDIT: DONE

I think maybe there needs to be a generic status check for the whole repository? If there is, then the role-specific one may be unneeded.