In addition to skipping animations when a related style doesn't Exist, now checks to see if animation styles are Empty as well.
This resolves a case where the Gutenberg End to End tests were failing, due to running with animations disabled.
This change should also help some users who are intentionally overriding styles to remove animations.
See https://github.com/WordPress/gutenberg/issues/32024 for the original Gutenberg issue.
Props zieladam, isabel_brison, kevin940726, desrosj, mikeschroder.
Fixes#53562.
See #53542.
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