Fix imutable pattern in EmitterSettings.SkipAnchorName

[FSDKO]

In class EmitterSettings the imutable pattern is not implemented consistent. SkipAnchorName is not handled correct.

The following test fails (this ist not a big thing):

var settings1 = new EmitterSettings();
var settings2 = settings1.WithoutAnchorName();
Assert.IsFalse(settings1.SkipAnchorName);

Reason: The method WithoutAnchorName() does not create a new instance like all other Methods.

The following test also fails - and this is a trap:

var settings = new EmitterSettings().WithoutAnchorName().WithBestIndent();
Assert.IsTrue(settings.SkipAnchorName);

Reason: all other Method don't give SkipAnchorName into the ctor.

[aaubry]

Thanks!

[github-actions]

This heature has been released in version 11.0.1.