* upgrade sqlalchemy to 2.0
* rewrite all db models to sqla 2.0 mapping api
* fix some importing and typing weirdness
* fix types of a lot of nullable columns
* remove get_ref methods
* fix issues found by tests
* rewrite all queries in repository_recipe to 2.0 style
* rewrite all repository queries to 2.0 api
* rewrite all remaining queries to 2.0 api
* remove now-unneeded __allow_unmapped__ flag
* remove and fix some unneeded cases of "# type: ignore"
* fix formatting
* bump black version
* run black
* can this please be the last one. okay. just. okay.
* fix repository errors
* remove return
* drop open API validator
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Co-authored-by: Sören Busch <fleshgolem@gmx.net>