Update black, and run auto formatting over the codebase (#9381)

- Update black version to the latest
 - Run black auto formatting over the codebase
    - Run autoformatting according to [`docs/code_style.md
`](80d6dc9783/docs/code_style.md)
 - Update `code_style.md` docs around installing black to use the correct version

tests/rest/client/v1/test_typing.py

@@ -37,7 +37,9 @@ class RoomTypingTestCase(unittest.HomeserverTestCase):
     def make_homeserver(self, reactor, clock):
 
         hs = self.setup_test_homeserver(
-            "red", federation_http_client=None, federation_client=Mock(),
+            "red",
+            federation_http_client=None,
+            federation_client=Mock(),
         )
 
         self.event_source = hs.get_event_sources().sources["typing"]