upgrade black version (#4486)

Manually removed a number of trailing commas to prevent black from unnecessarily
exploding some collections.

stdlib/3/http/client.pyi

@@ -131,7 +131,7 @@ class _HTTPConnectionProtocol(Protocol):
         ) -> HTTPConnection: ...
     else:
         def __call__(
-            self, host: str, port: Optional[int] = ..., timeout: float = ..., source_address: Optional[Tuple[str, int]] = ...,
+            self, host: str, port: Optional[int] = ..., timeout: float = ..., source_address: Optional[Tuple[str, int]] = ...
         ) -> HTTPConnection: ...
 
 class HTTPConnection: