Can't install plugins
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The Homebridge Raspberry Pi image is just Raspbian Linux with Homebridge installed as a service.
If you are facing an issue that is not Homebridge related you should look elsewhere for support.
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**Describe The Bug:**
```sh
USER: pi
DIR: /usr/local/lib
CMD: sudo -E -n npm install homebridge-dummy@latest


Error: forkpty(3) failed.
```
<!-- A clear and concise description of what the bug is. -->

**To Reproduce:**
Search for any plugin and attempt to install

**Expected behavior:**
plugin installs.

**Logs:**
```
[8/1/2020, 17:55:38] [Config] Running Command: sudo -E -n npm install homebridge-dummy@latest
[8/1/2020, 17:55:38] [Config] Error: forkpty(3) failed.
```


**Screenshots:**
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**Environment:**

* **Homebridge Raspberry Pi Image Version**: v1.0.7
* **Node.js Version**: v12.18.3
* **NPM Version**: 6.14.6
* **Homebridge Version**: 1.1.1
* **Homebridge Config UI X Plugin Version**: v4.24.0

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