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
`](https://github.com/matrix-org/synapse/blob/80d6dc9783aa80886a133756028984dbf8920168/docs/code_style.md)
 - Update `code_style.md` docs around installing black to use the correct version

1 files changed, 5 insertions, 2 deletions

diff --git a/synapse/storage/databases/main/registration.py b/synapse/storage/databases/main/registration.py
index 8405dd460f..07e219aaed 100644
--- a/synapse/storage/databases/main/registration.py
+++ b/synapse/storage/databases/main/registration.py
@@ -79,13 +79,16 @@ class RegistrationWorkerStore(CacheInvalidationWorkerStore):
         # call `find_max_generated_user_id_localpart` each time, which is
         # expensive if there are many entries.
         self._user_id_seq = build_sequence_generator(
-            database.engine, find_max_generated_user_id_localpart, "user_id_seq",
+            database.engine,
+            find_max_generated_user_id_localpart,
+            "user_id_seq",
         )
 
         self._account_validity = hs.config.account_validity
         if hs.config.run_background_tasks and self._account_validity.enabled:
             self._clock.call_later(
-                0.0, self._set_expiration_date_when_missing,
+                0.0,
+                self._set_expiration_date_when_missing,
             )
 
         # Create a background job for culling expired 3PID validity tokens