[chores] Upgrade drf-yasg~=1.21.0 openwisp#306

Removed the workaround for DRF-yasg.

Closes openwisp#306

Author: sassy-bugs

openwisp_utils/storage.py

@@ -7,20 +7,6 @@
 
 
 class FileHashedNameMixin:
-    # Workaround for DRF-yasg: https://github.com/axnsan12/drf-yasg/issues/761.
-    # TODO: Remove this when DRF-Yasg introduces proper Django 4.0 support.
-    patterns = (
-        (
-            "*.css",
-            (
-                "(?P<matched>url\\(['\"]{0,1}\\s*(?P<url>.*?)[\"']{0,1}\\))",
-                (
-                    "(?P<matched>@import\\s*[\"']\\s*(?P<url>.*?)[\"'])",
-                    '@import url("%(url)s")',
-                ),
-            ),
-        ),
-    )
 
     default_excluded_patterns = ['leaflet/*/*.png']
     excluded_patterns = default_excluded_patterns + getattr(

setup.py

@@ -62,7 +62,7 @@
         'rest': [
             'djangorestframework~=3.13.0',
             'django-filter~=22.1',  # django-filter uses CalVer
-            'drf-yasg~=1.20.0',
+            'drf-yasg~=1.21.0',
         ],
         'celery': ['celery~=5.2.3'],
     },