System.Runtime.Serialization.Xml.Canonicalization tests don't build or run

[ViktorHofer]

Regressed with dotnet/corefx#31946

https://github.com/dotnet/runtime/blob/main/src/libraries/System.Runtime.Serialization.Xml/tests/Canonicalization/System.Runtime.Serialization.Xml.Canonicalization.csproj don't build or run.

The arcade convention only looks at projects with certain file name suffixes: ".Tests", ".UnitTests", ".IntegrationTests": https://github.com/dotnet/arcade/blob/79fe26cb443b349dced1e03c904783e040115ce9/src/Microsoft.DotNet.Arcade.Sdk/tools/Tests.props#L4-L17