Add .NET 8 / .NET 10 as TFMs

[Sella-GH]

Hello,

this Library is featured in the Microsoft Documentation about ASP.NET Core Identity Multi-Factor Authentication.

Then I looked over the repo and saw that the package is mainly available and compiled for .NET 6. In the state of it being EoL since November 2024 I took the little effort to upgrade the TFMs to support .NET 8 and .NET 10 too. I also upgraded the NuGet packages so they're being available in the newest versions.

All tests are passing despite the .NET 6 ones won't even run, it just discovers no test available strangely.

Open Question

Since all of the Demo projects currently build as .NET 8 compatible my suggestion would be to throw out .NET 6 completely and only support the current LTS versions. This also allows to use newer Language Features like Collection Expressions etc.

[Copilot]

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[manuelbl]

Thanks for your PR. I will look into it.

For the library itself, there is probably no advantage in building it for a more recent .NET version. It's compatible anyway. The only reason it is built for .NET 6 and not just for .NET Standard 2.0 is that trimming was a requested feature and trimming is only available starting with .NET 6.

The examples are different. It could make sense to upgrade them. But at the same time, there are a lot of library users that still use .NET Framework 4.x. If they use the examples, they already have to downgrade the code to older language features. Likely, some of the examples needs both a .NET Framework 4.x version and one with a recent version of C#.