New majors prevent branch creation/switching

[internalsystemerror]

Bug Report

Q	A
Version(s)	1.19.0

Summary

When a release is made and a new major release branch exists, the new branch/milestones are not created or switched to. This was introduced by #210 not working as intended.

[DanielBadura]

We also noticed this, see here for the failing action: https://github.com/patchlevel/event-sourcing/actions/runs/4023294752/jobs/6913984557