Fix lint issues.

Author: pujawadare

google/api_core/bidi.py

@@ -285,7 +285,7 @@ def close(self):
             self.call.cancel()
 
         # Put None in request queue to signal termination.
-        self._request_queue.put(None)        
+        self._request_queue.put(None)
         self._request_generator = None
         self._callbacks = []
         # Don't set self.call to None. Keep it around so that send/recv can

google/api_core/bidi_async.py

@@ -201,7 +201,7 @@ async def close(self) -> None:
             self.call.cancel()
 
         # Put None in request queue to signal termination.
-        await self._request_queue.put(None)        
+        await self._request_queue.put(None)
         self._request_generator = None
         self._callbacks = []
         # Don't set self.call to None. Keep it around so that send/recv can