Merge branch 'bump-drf-spectacular' into 'master'

Bump Python requirement drf-spectacular to 0.13.1

See merge request !1210

requirements.txt

@@ -10,7 +10,7 @@ django-enumfields==2.0.0
 django-redis==4.12.1
 django-rq==2.4.0
 djangorestframework==3.12.2
-drf-spectacular==0.12.0
+drf-spectacular==0.13.1
 elasticsearch-dsl>=6.0.0,<7.0.0
 gitpython==3.1.11
 python-gitlab==1.7.0