fix: Race condition when using destroy

In a case were destroy is being called by a higher priority task set the
STOPPED_BIT before seting the state would lead to a crash.

Author: euripedesrocha

mqtt_client.c

@@ -1763,8 +1763,8 @@ static void esp_mqtt_task(void *pv)
     }
     esp_transport_close(client->transport);
     outbox_delete_all_items(client->outbox);
-    xEventGroupSetBits(client->status_bits, STOPPED_BIT);
     client->state = MQTT_STATE_DISCONNECTED;
+    xEventGroupSetBits(client->status_bits, STOPPED_BIT);
 
     vTaskDelete(NULL);
 }