Reset RPC min broadcast ID when node module resets

Otherwise, bridge module will ignore events until new broadcast ID
catches up to the old one

matrix_appservice_kakaotalk/rpc/rpc.py

@@ -166,6 +166,8 @@ class RPCClient:
         self._on_disconnect()
 
     def _on_disconnect(self) -> None:
+        self._req_id = 0
+        self._min_broadcast_id = 0
         self._reader = None
         self._writer = None
         self._is_connected.clear()