QuACS data source adapter, multisemester support, and bug fixes

[io12]

WaterDrop 2.0 is backwards-incompatible with 1.*, so malg crashes without explicitly using the older version.

Core-consumer assumes that karafka allows multiple topics for the same consumer, which isn't true with the current version. Fixing this allows multi-semester support to work.

Also, the old banner adapter's upstream data is not being updated anymore. This PR adds a new QuACS adapter allows YACS to get up-to-date data.