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

synapse/storage/databases/main/transactions.py

@@ -64,8 +64,7 @@ class TransactionWorkerStore(SQLBaseStore):
 
 
 class TransactionStore(TransactionWorkerStore):
-    """A collection of queries for handling PDUs.
-    """
+    """A collection of queries for handling PDUs."""
 
     def __init__(self, database: DatabasePool, db_conn, hs):
         super().__init__(database, db_conn, hs)
@@ -299,7 +298,10 @@ class TransactionStore(TransactionWorkerStore):
             )
 
     async def store_destination_rooms_entries(
-        self, destinations: Iterable[str], room_id: str, stream_ordering: int,
+        self,
+        destinations: Iterable[str],
+        room_id: str,
+        stream_ordering: int,
     ) -> None:
         """
         Updates or creates `destination_rooms` entries in batch for a single event.
@@ -394,7 +396,9 @@ class TransactionStore(TransactionWorkerStore):
         )
 
     async def get_catch_up_room_event_ids(
-        self, destination: str, last_successful_stream_ordering: int,
+        self,
+        destination: str,
+        last_successful_stream_ordering: int,
     ) -> List[str]:
         """
         Returns at most 50 event IDs and their corresponding stream_orderings
@@ -418,7 +422,9 @@ class TransactionStore(TransactionWorkerStore):
 
     @staticmethod
     def _get_catch_up_room_event_ids_txn(
-        txn: LoggingTransaction, destination: str, last_successful_stream_ordering: int,
+        txn: LoggingTransaction,
+        destination: str,
+        last_successful_stream_ordering: int,
     ) -> List[str]:
         q = """
                 SELECT event_id FROM destination_rooms
@@ -429,7 +435,8 @@ class TransactionStore(TransactionWorkerStore):
                 LIMIT 50
             """
         txn.execute(
-            q, (destination, last_successful_stream_ordering),
+            q,
+            (destination, last_successful_stream_ordering),
         )
         event_ids = [row[0] for row in txn]
         return event_ids