Include Django 6.0 in test matrix

Author: intgr

.github/workflows/test.yml

@@ -204,6 +204,11 @@ jobs:
       matrix:
         python-version: ['3.10', '3.11', '3.12', '3.13']
         django-version: ['5.0', '5.1', '5.2']
+        include:
+          - python-version: '3.12'
+            django-version: '6.0'
+          - python-version: '3.13'
+            django-version: '6.0'
     steps:
       - uses: actions/checkout@v6
       - name: Setup system dependencies