Hygrothermograph 2 / LYWSD03MMC cannot be detected
### Expected Behavior
Homebridge is able to find my Hygrothermograph 2

### Current Behavior
Homebridge is not able to find my Hygrothermograph 2. In homebridge log:
```
[5/24/2020, 12:52:25 AM] [Temperature & Humidity] Initializing Hygrotermograph accessory...
[5/24/2020, 12:52:25 AM] [Temperature & Humidity] Start scanning.
```

Then no more log lines appear...

### Steps to Reproduce (for bugs)
Nothing special, install this plugin, config it, then restart homebridge

### Versions
<!-- Please run commands and include versions below. -->
- **homebridge**: `1.1.0`
- **homebridge-mi-hygrothermograph**: `homebridge-mi-hygrothermograph@3.0.0`
- **node**:       `v12.16.3`
- **OS**:         pi@raspberrypi:~ $ cat /etc/os-release
PRETTY_NAME="Raspbian GNU/Linux 10 (buster)"
NAME="Raspbian GNU/Linux"
VERSION_ID="10"
VERSION="10 (buster)"
VERSION_CODENAME=buster
ID=raspbian
ID_LIKE=debian
HOME_URL="http://www.raspbian.org/"
SUPPORT_URL="http://www.raspbian.org/RaspbianForums"
BUG_REPORT_URL="http://www.raspbian.org/RaspbianBugs"


### Configuration
```json
    "accessories": [
        {
            "name": "Temperature & Humidity",
            "accessory": "Hygrotermograph",
            "address": "A4:C1:38:xx:xx:xx",
            "bindKey": "AB3198E7AF704987025XXXXXXXXXXXX"
        }
    ]
```
I got bindKey by following [this instruction](https://community.home-assistant.io/t/xiaomi-passive-ble-monitor-sensor-platform/177352/117?u=magalex)

I specified address because I have multiple Hygrothermograph 2 devices

### Homebridge Log / Command Output
```
[5/24/2020, 12:52:21 AM] [HB Supervisor] Starting Homebridge with extra flags: -I
[5/24/2020, 12:52:21 AM] [HB Supervisor] Started Homebridge v1.1.0 with PID: 7692
[5/24/2020, 12:52:22 AM] Loaded config.json with 1 accessories and 1 platforms.
[5/24/2020, 12:52:22 AM] ---
[5/24/2020, 12:52:23 AM] Loaded plugin: homebridge-config-ui-x@4.20.0
[5/24/2020, 12:52:23 AM] Registering platform 'homebridge-config-ui-x.config'
[5/24/2020, 12:52:23 AM] ---
[5/24/2020, 12:52:23 AM] Loaded plugin: homebridge-mi-hygrothermograph@3.0.0
[5/24/2020, 12:52:25 AM] Registering accessory 'homebridge-mi-hygrothermograph.Hygrotermograph'
[5/24/2020, 12:52:25 AM] ---
[5/24/2020, 12:52:25 AM] Loading 1 platforms...
[5/24/2020, 12:52:25 AM] [Config] Initializing config platform...
[5/24/2020, 12:52:25 AM] [Config] Running in Service Mode
[5/24/2020, 12:52:25 AM] Loading 1 accessories...
[5/24/2020, 12:52:25 AM] [Temperature & Humidity] Initializing Hygrotermograph accessory...
Setup Payload:
X-HM://XXXXXXXXXXX
Enter this code with your HomeKit app on your iOS device to pair with Homebridge:
                       
    ┌────────────┐     
    │ XXX-XX-XXX │     
    └────────────┘     
                       
[5/24/2020, 12:52:25 AM] Homebridge is running on port 51694.
[5/24/2020, 12:52:25 AM] [Temperature & Humidity] Start scanning.
```
