App Check support

[dmitry-bym]

Is it posible to add App check support? I urgently needed AppCheck and had to write everything myself. So i can just create pr and implement that step by step. My company needs this, but since I do it anyway, it would be nice to do it for everyone

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[lahirumaramba]

Hey @dmitry-bym we do not have any immediate plans to add App Check support to the .NET SDK. However, we would be glad to review any PRs if you would like to contribute to the codebase. You can also find the required steps to verify an App Check token on this blog post (see under "Verifying App Check tokens in other backend resources"). Thank you!

[large]

There is a PR with this feature: #374
Isn't the quality good enough for implementation?