Move Attribute* classes to Component\Utility

Benji Fisherrequested to merge
issue/drupal-2664570:2664570-split-attribute-class into main

Rename AttributeArray, AttributeBoolean, AttributeString, and AttributeValueBase to HtmlAttribute* in Drupal\Component\Utility. Deprecate the old names with core.moved_classes.

Closes #2664570

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