Homebridge 1.3.0 reports a warning for the characteristic 'On': SET handler
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**Describe The Problem:**
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Upgraded to Homebridge v1.3.0 today.
Noted that Homebridge is reporting a warning for homebridge-camera-ffmpeg 

**To Reproduce:**
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1. Ensure Homebridge v1.3.0 is installed
2. View Homebridge logs

**Logs:**
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```
[20/02/2021, 12:52:12] [homebridge-camera-ffmpeg] This plugin generated a warning from the characteristic 'On': SET handler returned write response value, though the characteristic doesn't support write response! See https://git.io/JtMGR for more info.
```


**Environment:**

* **Node.js Version**: v14.15.5
* **NPM Version**: v6.14.11
* **Homebridge Version**: v1.3.0
* **Homebridge Camera FFmpeg Version**: v3.0.6
* **Homebridge Config UI X Plugin Version**: v4.39.0 
* **Operating System**: Raspbian GNU/Linux Buster (10)

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