Clears pool._working_addr if closing connection due to consecutive exceptions

This change will help alleviate any issues in an HA configuration where
the server IP is cached by the pool initialization.

Author: egalpin

asyncpg/pool.py

@@ -282,6 +282,7 @@ async def maybe_close_bad_connection(self, exc_type):
             if self._consecutive_exceptions > self._max_consecutive_exceptions:
                 await self.close()
                 self._consecutive_exceptions = 0
+                self._pool._working_addr = None
 
 
 class Pool: