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, 3 insertions, 3 deletions

diff --git a/synapse/storage/databases/state/store.py b/synapse/storage/databases/state/store.py

index 89cdc84a9c..b16b9905d8 100644
--- a/synapse/storage/databases/state/store.py
+++ b/synapse/storage/databases/state/store.py
@@ -48,8 +48,7 @@ class _GetStateGroupDelta(
 
 
 class StateGroupDataStore(StateBackgroundUpdateStore, SQLBaseStore):
-    """A data store for fetching/storing state groups.
-    """
+    """A data store for fetching/storing state groups."""
 
     def __init__(self, database: DatabasePool, db_conn, hs):
         super().__init__(database, db_conn, hs)
@@ -89,7 +88,8 @@ class StateGroupDataStore(StateBackgroundUpdateStore, SQLBaseStore):
             50000,
         )
         self._state_group_members_cache = DictionaryCache(
-            "*stateGroupMembersCache*", 500000,
+            "*stateGroupMembersCache*",
+            500000,
         )
 
         def get_max_state_group_txn(txn: Cursor):