[EnC] Add test case for deleting custom attributes using ApplyUpdate

[lambdageek]

Now that #54060 and #54619 have been merged, we can add new tests to validate that CoreCLR ApplyUpdate behaves correctly when custom attributes are deleted.

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Issue Details

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Now that #54060 has been merged, we can add new tests to validate that CoreCLR ApplyUpdate behaves correctly when custom attributes are deleted.

Once we have the extra tests, we need to add ChangeCustomAttributes to the string here:

runtime/src/coreclr/System.Private.CoreLib/src/System/Reflection/Metadata/AssemblyExtensions.cs

Lines 85 to 89 in 636988a

	internal static string GetApplyUpdateCapabilities()
	{
	return "Baseline AddMethodToExistingType AddStaticFieldToExistingType AddInstanceFieldToExistingType NewTypeDefinition";
	}
	}

Author:	lambdageek
Assignees:	-
Labels:	area-Diagnostics-coreclr
Milestone:	6.0.0

[noahfalk]

@mikem8361

[lambdageek]

I think the new capability went in (#54619). But we don't have a testcase.