[Device] Aqara TVOC air quality monitor (VOCKQJK11LM)
**Device description**
Zigbee Model: lumi.airmonitor.acn01
Zigbee Manufacturer: LUMI
Description: Aqara TVOC air quality monitor
Manufacturer: Xiaomi
Model: VOCKQJK11LM

**Supported in Zigbee2MQTT?**
Yes it is already in master branch, by this PR: https://github.com/Koenkk/zigbee-herdsman-converters/pull/2815

**Device model / Exposes information**
```json
    "definition": {
      "description": "Aqara TVOC air quality monitor",
      "exposes": [
        {
          "access": 1,
          "description": "Remaining battery in %",
          "name": "battery",
          "property": "battery",
          "type": "numeric",
          "unit": "%",
          "value_max": 100,
          "value_min": 0
        },
        {
          "access": 1,
          "description": "Measured temperature value",
          "name": "temperature",
          "property": "temperature",
          "type": "numeric",
          "unit": "°C"
        },
        {
          "access": 1,
          "description": "Measured relative humidity",
          "name": "humidity",
          "property": "humidity",
          "type": "numeric",
          "unit": "%"
        },
        {
          "access": 1,
          "description": "Measured VOC value",
          "name": "voc",
          "property": "voc",
          "type": "numeric",
          "unit": "ppb"
        },
        {
          "access": 1,
          "description": "Link quality (signal strength)",
          "name": "linkquality",
          "property": "linkquality",
          "type": "numeric",
          "unit": "lqi",
          "value_max": 255,
          "value_min": 0
        }
      ],
      "model": "VOCKQJK11LM",
      "supports_ota": false,
      "vendor": "Xiaomi"
    },
```

**Missing features/functionality**
Only one thing is missing in Homekit, the VOC.

**Suggested services and characteristics**
I'm not sure here, but when conected this device via aquara hub it is exposed to HomeKIt like TVOC Sensor in climate section:
![tvoc](https://user-images.githubusercontent.com/302761/127710176-5a901aec-5394-41c3-ac5b-8d884ba00923.png)
