Plugin Crashes Due to Missing FFmpeg.
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**Describe The Problem:**
On update to 4.4.4 when attempting to start a stream the plugin crashes the child bridge.

**To Reproduce:**
Start a steam on any iOS or MacOS device

**Logs:**

[1/2/2022, 6:21:36 PM] [Homebridge UI] Running Command: npm install -g homebridge-unifi-protect@latest
Error: Command failed with ENOENT: ffmpeg -codecs
spawn ffmpeg ENOENT
    at Process.ChildProcess._handle.onexit (node:internal/child_process:282:19)
    at onErrorNT (node:internal/child_process:477:16)
    at processTicksAndRejections (node:internal/process/task_queues:83:21)
[1/2/2022, 6:22:27 PM] [homebridge-unifi-protect] Child bridge process ended
[1/2/2022, 6:22:27 PM] [homebridge-unifi-protect] Process Ended. Code: 1, Signal: null


**Environment:**

* **Homebridge Version:** 1.3.9
* **Node Version:** 16.13.1
* **Homebridge-UniFi-Protect Plugin Version:** 4.4.4
* **UniFi Protect Version:** 1.20.3
* **UniFi Protect Controller Type:** UDMP
* **UniFi Protect Controller Firmware Version:** 1.11.0
* **Apple Device and iOS / macOS / iPadOS / tvOS Version:** 15.2
* **Operating System and OS Version:**  macOS

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