don't run drawing tests on Mono

[adamsitnik]

In #107553 a group of tests was failing because Bitmap is not supported on Mono.

System.Runtime.Serialization.Formatters.Tests.BinaryFormatterTests.ValidateAgainstBlobs [FAIL]
      System.TypeInitializationException : The type initializer for 'System.Drawing.DrawingCom' threw an exception.
      ---- System.PlatformNotSupportedException : Operation is not supported on this platform.
      Stack Trace:
           at System.Drawing.Bitmap..ctor(Stream stream, Boolean useIcm)
           at System.Drawing.Bitmap..ctor(Stream stream)

The code was already using a guard for that:

https://github.com/dotnet/runtime/blob/06a6ea78fbe99fd86f2f46df9b046cb4c4ea18a7/src/libraries/System.Runtime.Serialization.Formatters/tests/BinaryFormatterTestData.cs#L1346-L1349

I decided to update the logic behind PlatformDetection.IsDrawingSupported as I assumed it's simply not supported and could help in other places. But I need a confirmation from @matouskozak or someone else from the Mono team.

fixes #107553

[adamsitnik]

/azp run runtime-extra-platforms

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[jkotas]

LGTM

System.Drawing depends on ComWrappers that are not supported on Mono.