Currently there are at least three different authentication methods in use with fedpkg(+git?), that is very confusing. Could we unify those to become less, ideally only one?

Examples:
- git operations: ssh key
- fedpkg new-source: kerberos? (I know I need to run the kinit command when if fails. With the very short lifespan nowadays it becomes kind of annoying to refresh it every time)
- fedpkg fork: Api token
- pushing to the forked branch: Popup browser window (that actually feels quite convenient, but is the newest addition to the authentication zoo iirc)