What to do with MSTest MTP test templates in .NET 10? #50054
Description
Today, the MTP templates just set extra properties in csproj.
In .NET 10, it's more involved. We always want users to use the new dotnet test experience via dotnet.config and never the old experience. As a result, we don't want to set TestingPlatformDotnetTestSupport any more, and we want to have a mechanism to add dotnet.config at repo/solution root, if it's not already present.
Another note, we want to align releasing MTP v2/MSTest v4 with .NET 10 SDK release. We also want the templates in .NET 10 SDK to use MSTest v4, so MSTest will probably have to release a bit before .NET 10 SDK so we have time to insert.