airpurifier_miot: force aqi update prior fetching data (#1282)

* airpurifier_miot: force aqi update prior fetching data

* use better name for aqi sensor update duration, bump the duration to five seconds

* Add explanation why we adjust the update duration for mb3

miio/airpurifier_miot.py

@@ -51,6 +51,7 @@
     # AQI (siid=13)
     "purify_volume": {"siid": 13, "piid": 1},
     "average_aqi": {"siid": 13, "piid": 2},
+    "aqi_realtime_update_duration": {"siid": 13, "piid": 9},
     # RFID (siid=14)
     "filter_rfid_tag": {"siid": 14, "piid": 1},
     "filter_rfid_product_id": {"siid": 14, "piid": 3},
@@ -406,6 +407,11 @@ class AirPurifierMiot(BasicAirPurifierMiot):
     )
     def status(self) -> AirPurifierMiotStatus:
         """Retrieve properties."""
+        # Some devices update the aqi information only every 30min.
+        # This forces the device to poll the sensor for 5 seconds,
+        # so that we get always the most recent values. See #1281.
+        if self.model == "zhimi.airpurifier.mb3":
+            self.set_property("aqi_realtime_update_duration", 5)
 
         return AirPurifierMiotStatus(
             {