[release pipeline] Add .NET 10 validation pipeline

[mthalman]

PR validation for the SB release pipeline is done by a set of .NET version-specific pipelines. There should be one configured for .NET 10 once Preview 1 has been staged (internal link).

Once this gets added, AzDO should be updated to include this as an optional check for PRs at https://dev.azure.com/dnceng/internal/_settings/repositories?repo=c02a7e43-a426-455b-bba9-335409c459ba&_a=policiesMid&refs=refs/heads/main (internal link).

[dotnet-issue-labeler]

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[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.