Update icon request: Unity real time 3D engine
### Acknowledgement

- [X] I have searched through both open and closed issues and confirm that this icon has not been requested earlier.

### Icon

The icon has been updated, so this would need to replace [the already existing fa-unity](https://forkaweso.me/Fork-Awesome/icon/unity/).

![safari-pinned-tab](https://user-images.githubusercontent.com/1271004/216845242-95c3c01e-5a1b-4a0e-9164-f6b83dab9b23.svg)

![DP_brand_logo_tab](https://user-images.githubusercontent.com/1271004/216845231-c3132b54-73ea-4b7f-b489-125ec8be0b2b.png)


### Name suggestion

fa-unity

### Use-case

Game developers who wish to link to Unity accreditations or perhaps those who host games on their play.unity.com platform would benefit from it.

Personally, I'd like to link to this platform on the sidebar of my website.

### Additional information for brand icons

See Unity's brand guidelines [here](https://brandguide.brandfolder.com/unity/unitylogo).

Previously, the Unity logo was added with issue [#178](https://github.com/ForkAwesome/Fork-Awesome/issues/178).