Use git version of django-taggit. We need

https://github.com/jazzband/django-taggit/commit/c76d4d2069b40559bb7259f31e8f74656ade8d3a

requirements.txt

@@ -9,7 +9,7 @@ django-haystack             # debian: python3-django-haystack
 django-ical                 # NOT IN DEBIAN
 django-imagekit             # debian (buster): python3-django-imagekit
 django-mailbox              # NOT IN DEBIAN
-django-taggit
+git+https://github.com/jazzband/django-taggit.git
 djangorestframework         # debian: python-djangorestframework
 feedparser                  # debian: python3-feedparser
 flake8                      # debian: flake8