TestBackAndForthConversionWithAlphaNoInterleave disabled

[michaelgsharp]

This issue is to track that the test TestBackAndForthConversionWithAlphaNoInterleave has been disabled for stability in the ARM legs of the CI builds. As soon as we swap away from System.Drawing we can revisit this test (as it will need to be updated anyways).

[michaelgsharp]

Also disabling TestBackAndForthConversionWithoutAlphaNoInterleave for same reasons.

[michaelgsharp]

Also disabling TestBackAndForthConversionWithAlphaNoInterleaveNoOffset for same reasons.
Also disabling TestBackAndForthConversionWithoutAlphaInterleaveNoOffset for same reasons.