Deprecate "Nur aktuelles Semester anzeigen"

[asjg-study]

The box in Options is set by default but only works for L2P. For old farts like me, it is not necessarily clear that there is one L2P semester actually there, leading me to assume the sync with L2P didn't work.

I'd propose to just not use the option anymore and just show everything reachable for that student

If anyone's feeling ambitious, they could try to make it work for moodle

Cheers!