🚀 Feature: Add Unity plugin to showcase

[AlexMeesters]

🔖 Feature description

I have made a plugin for Unity to make it easy to login/register/verify email, generate a JWT and store a user session on disk.
The Github repository in question: https://github.com/AlexMeesters/unity-appwrite-plugin

🎤 Pitch

This plugin might be useful for users that are making a Unity game/project.
Using the JWT as a means to authenticate the user with matchmaking or game servers.
More features may get added as well in the future, depending on project needs.
For now this might fit best in the Showcase tab.

👀 Have you spent some time to check if this issue has been raised before?

• I checked and didn't find similar issue

🏢 Have you read the Code of Conduct?

• I have read the Code of Conduct

[AlexMeesters]

Did a pull request instead.