Fixed typos in test names and a comment.

tests/aggregation_regress/tests.py

@@ -1298,7 +1298,7 @@ class AggregationTests(TestCase):
         )
 
     @skipUnlessDBFeature('allows_group_by_selected_pks')
-    def test_aggregate_ummanaged_model_columns(self):
+    def test_aggregate_unmanaged_model_columns(self):
         """
         Unmanaged models are sometimes used to represent database views which
         may not allow grouping by selected primary key.

tests/builtin_server/tests.py

@@ -66,7 +66,7 @@ def wsgi_app_file_wrapper(environ, start_response):
 
 class WSGIFileWrapperTests(TestCase):
     """
-    The wsgi.file_wrapper works for the builting server.
+    The wsgi.file_wrapper works for the builtin server.
 
     Tests for #9659: wsgi.file_wrapper in the builtin server.
     We need to mock a couple of handlers and keep track of what

tests/prefetch_related/tests.py

@@ -1363,7 +1363,7 @@ class Ticket21760Tests(TestCase):
         self.assertNotIn(' JOIN ', str(queryset.query))
 
 
-class DirectPrefechedObjectCacheReuseTests(TestCase):
+class DirectPrefetchedObjectCacheReuseTests(TestCase):
     """
     prefetch_related() reuses objects fetched in _prefetched_objects_cache.
 

tests/requests/tests.py

@@ -458,7 +458,7 @@ class RequestsTests(SimpleTestCase):
         self.assertEqual(request.read(13), b'--boundary\r\nC')
         self.assertEqual(request.POST, {'name': ['value']})
 
-    def test_POST_immutable_for_mutipart(self):
+    def test_POST_immutable_for_multipart(self):
         """
         MultiPartParser.parse() leaves request.POST immutable.
         """

tests/schema/tests.py

@@ -2574,7 +2574,7 @@ class SchemaTests(TransactionTestCase):
                 self.assertIsNone(field.default)
 
     @unittest.skipIf(connection.vendor == 'sqlite', 'SQLite naively remakes the table on field alteration.')
-    def test_alter_field_default_doesnt_perfom_queries(self):
+    def test_alter_field_default_doesnt_perform_queries(self):
         """
         No queries are performed if a field default changes and the field's
         not changing from null to non-null.