Fix async driver waiting for OS on closing half-open socket (#1315)

This change aligns the async driver better with the sync driver.
When a socket is closed, we don't want to wait until the OS acknowledges that
the channel has been fully torn down. It's sufficient to initiate the closure.
The rest we'll leave to the OS's TCP stack (and potentially other intermediates
such as TLS wrappers) or the async runtime to figure out in the background.

Author: robsdedude

src/neo4j/_async_compat/network/_bolt_socket.py

@@ -192,7 +192,6 @@ async def sendall(self, data):
 
     async def close(self):
         self._writer.close()
-        await self._writer.wait_closed()
 
     def kill(self):
         self._writer.close()