Non MI Professors unsupported

[CommanderStorm]

Describe the bug Currently, non-mi professors are unsupported. As such Professors as Prof. Henkel can't be added to courses are his => he won't hold a lecture for which he is not the admin for obvious reasons

Furthermore, It is unclear if they receive the beginning of semester emails, even if they have lectures in supported lecture halls

To Reproduce Steps to reproduce the behaviour:

1. Add a lecture
2. Try to add a lecturer as Prof. Henkel as admin
3. It does not allow me to add him

Expected behaviour The ability to and any TUM Student + lecturer (regardless of which school) as an admin

Screenshots If applicable, add screenshots to help explain your problem.

Additional context The emailing issue could be related to the course being split up between multiple lecturers

Last year this failed because https://github.com/TUM-Dev/gocast/issues/1000

[hmelder]

Adding a new professor to a new lecture requires the professor to login in at least once, in order for him to appear in the list.