Revert "Update dependency django-sass-processor to v1.2.1"

See merge request !1104

https://github.com/jrief/django-sass-processor/issues/159

This reverts commit 8744e679.

Save detailed information for Celery tasks

See merge request !1103

Resolve "Invitations: Person invitation throws unexpected error"

Closes #689

See merge request !1019

# Conflicts:
#   CHANGELOG.rst

Fix DoesNotExistError in InvitePerson view

See merge request !1101

Fix typo

See merge request !1102

Fix typo

See merge request !1100

Add base template for plain prints and optimize PDF generation

See merge request !991

# Conflicts:
#   CHANGELOG.rst

Update dependency django-sass-processor to v1.2.1

See merge request !1014

Resolve "Show also group ownerships on person detail page"

Closes #694

See merge request !1094

Update dependency graphene-django to v3

See merge request !1096

Update dependency django-invitations to v2

See merge request !1097

Drop support for GitHub

See merge request !1092

Resolve "aleksis/core/forms.py: Weird phrase in ValidationError()"

Closes #691

See merge request !1091

Resolve "[OIDC] "profile" scope should use avatar instead of photo"

Closes #729

See merge request !1088