Source generator for the version of this project

[andreaTP]

Fixes #2147

I have attempted and failed to use the Microsoft.Build package (dependencies and other errors even using it in the tests...).

[baywet]

Thanks for the contribution!

In addition to my comments, a entry in the changelog is missing.

[andreaTP]

Changelog added, @baywet if you find a reference for a different approach to the problem I'm up to look at it 🙂 .
It was not "trivial" to get it working, but highly instructive on .NET toolchain etc.

[baywet]

@andreaTP I just realized that the dotnet request adapter also relies on assembly metadata. You might want to replicate the change you've made here over there and the github search functionality won't work in your scenario because of that.
https://github.com/microsoft/kiota-http-dotnet/blob/10863ce94fabfcab28fa679aa4a791c02f999458/src/Middleware/Options/UserAgentHandlerOption.cs#L28