Support dotnet 10

[Frassle]

dotnet 10 is due to release this month. We should update testing to ensure we can support dotnet 10 when its released.

[ThaDaVos]

I just did the upgrade to DotNet 8 in my PR for NativeAoT Support by including System.Text.Json Source generators - I could do the Dotnet 10 upgrade too - in a separate or same PR:
#745

[Frassle]

So we've been trying to keep the core library targeting the oldest version possible so that we don't force a framework update on people. We might not officially support net6 anymore but forcing every user to net8 does have some risk. net10 is a definite no as we still need to support net8.

[ThaDaVos]

Then I think my PR with the changes to DotNet 8 (As it's the oldest supported LTS) is the best bet for now:
https://dotnet.microsoft.com/en-us/platform/support/policy/dotnet-core

[Frassle]

This was done by #743

[ThaDaVos]

Great that it was done @Frassle - but how about my NativeAoT fixes?

[Frassle]

Sorry we haven't had time to get back to them this month. I'll get them looked at again next month when I'm back from PTO.