Resolve "Paweljong doesn't appear in the frontend"

Closes #62

See merge request !57

Resolve "Register account menu point is not shown"

Closes #57

See merge request !52

# Conflicts:
#   aleksis/apps/paweljong/rules.py

Resolve "paweljong.generate_lists_rule does not exist"

Closes #55

See merge request !51

Resolve "Make sure InvoiceGroups exists when registering for event"

Closes #59

See merge request !55

Merge branch '54-view_registrations_rule-is-included-as-a-sufficient-rule-for-viewing-the-menu-even-though-it-is' into 'master'

Resolve "view_registrations_rule is included as a sufficient rule for viewing the menu even though it is not relevant"

Closes #54

See merge request !47

Revert "Update pyproject"

See merge request !48