Replace 6.0a1 refs with the stable release

Author: ulgens

.github/workflows/test.yml

@@ -133,7 +133,7 @@ jobs:
           # Install this project in editable mode, so that its package metadata can be queried
           pip install --editable .
           # Install the latest minor version of Django we support
-          pip install --pre "Django>=6.0a1"
+          pip install --pre "Django==6.0"
 
       - name: Check translation files are updated
         run: python -m simple_history.tests.generated_file_checks.check_translations

tox.ini

@@ -38,7 +38,7 @@ deps =
     dj50: Django>=5.0,<5.1
     dj51: Django>=5.1,<5.2
     dj52: Django>=5.2,<5.3
-    dj60: Django>=6.0a1,<6.1  # Use a1 to allow testing of the release candidates
+    dj60: Django>=6.0,<6.1
     djmain: https://github.com/django/django/tarball/main
     postgres: -rrequirements/postgres.txt
     mysql: -rrequirements/mysql.txt