Update poetry lockfile. Advances AlekSIS/official/AlekSIS#316.

See merge request !35

Update lockfile. Advances AlekSIS/official/AlekSIS#305.

See merge request !34

Update lockfile

See merge request !33

Currently translated at 2.2% (1 of 44 strings)

Translation: AlekSIS/AlekSIS-App-Untis
Translate-URL: https://translate.edugit.org/projects/aleksis/aleksis-app-untis/la/

Save year for week-related stuff

See merge request !32

Update dependency pytest to v6

See merge request !30

Update dependency flake8-isort to v4

See merge request !31

Resolve "Register different import tasks/methods"

Closes #8

See merge request !29

Close #8

Fix lint issues and reformat

See merge request !26

Update dependency isort to v5

See merge request !27

Reason: UNTIS school years are always one full year
and school terms also can be a half year.

Update dependency mysqlclient to v2

See merge request !25

Delete no-longer existing lessons

See merge request !23

Use subject object to match course groups

See merge request !22