chore(deps): update dependency djangorestframework to v3.15.2 [security]

Author: renovate[bot]

requirements.txt

@@ -110,7 +110,7 @@ django-treebeard==4.3
     # via wagtail
 django-webpack-loader==0.5.0
     # via -r requirements.in
-djangorestframework==3.11.2
+djangorestframework==3.15.2
     # via
     #   -r requirements.in
     #   wagtail