Refs #25415 -- Fixed/silenced check errors in Django's test suite.

tests/runtests.py

@@ -163,6 +163,10 @@ def setup(verbosity, test_labels, parallel):
     # tests.
     log_config['loggers']['django']['level'] = 'ERROR'
     settings.LOGGING = log_config
+    settings.SILENCED_SYSTEM_CHECKS = [
+        'fields.W342',  # ForeignKey(unique=True) -> OneToOneField
+        'fields.W901',  # CommaSeparatedIntegerField deprecated
+    ]
 
     warnings.filterwarnings(
         'ignore',

tests/test_runner/tests.py

@@ -204,8 +204,6 @@ class Ticket17477RegressionTests(AdminScriptTestCase):
 
 class Sqlite3InMemoryTestDbs(TestCase):
 
-    available_apps = []
-
     @unittest.skipUnless(all(db.connections[conn].vendor == 'sqlite' for conn in db.connections),
                          "This is an sqlite-specific issue")
     def test_transaction_support(self):