Move transistions-retarget.html to WPT
The test being moved is not testing compositor behavior and has
been ratified in the spec. Moving to WPT.
Bug: 350934898
Change-Id: Ie5d61173cd0c9a7c612dfd3b13688b5f28544b91
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5690516
Commit-Queue: Kevin Ellis kevers@chromium.org
Reviewed-by: David Awogbemila awogbemila@chromium.org
Cr-Commit-Position: refs/heads/main@{#1326069}