Doorbell Ring does not trigger when HomeBridge is on a Docker
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**Describe The Problem:**
Doorbell Ring does not trigger when HomeBridge is on a Docker

**To Reproduce:**
First everything works as expected including doorbell push and ringing to all HomePods when this plugin is used. However, when I place Homebridge on the docker (in my case Qnap NAS), video and others works fine and still very fast, but doorbell ring does not trigger on the homebridge.

The reason why I said doorbell ring does not trigger in the homebridge is because I have turned on "Enable.Doorbell.Trigger". Pushing this virtual switch from either Homebridge app or Apple Home app, HomePod mini does make sound. When I push physical doorbell, I do not see the virtual switch turns on. Hence, my conclusion is the link between Physical Doorbell (UniFi Protect) to Homebridge Plugin must be somehow bypassed/broken when Docker is used.

**Logs:**
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N/A (as nothing recorded/triggered in the log).

**Homebridge Configuration:**

"controllers": [
                {
                    "address": "192.168.1.1",
                    "password": "XXXXXXX",
                    "username": "XXXXXX"
                }
            ],
            "options": [
                "Enable.Doorbell.Trigger"
            ],
            "_bridge": {
                "username": "XXXXX",
                "port": 30399
            },
            "platform": "UniFi Protect"

**Screenshots:**
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N/A

**Environment:**

* **Homebridge Version: 1.3.4
* **Node Version: 14.16.0
* **Homebridge-UniFi-Protect Plugin Version: 4.3.5
* **UniFi Protect Version: 1.17.4 <!-- Read the Protect version line from https://unifi-controller/protect/settings -->
* **UniFi Protect Controller Type: UDMP <!-- UCKgen2+, UDMP, UNVR, etc. -->
* **UniFi Protect Controller Firmware Version: 1.9.0 <!-- Read the firmware line from https://unifi-controller/settings/general -->
* **Apple Device and iOS / macOS / iPadOS / tvOS Version: iPhone 12 Pro (iOS 14.4.1) <!-- Type of Apple device you're using and associated OS version -->
* **Operating System and OS Version: Docker (Qnap) <!-- Raspbian / Ubuntu / Debian / Windows / macOS / Docker -->

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