They are not transitionable:
https://drafts.csswg.org/css-transitions-1/#transitionable
There are some new failures in background-image-interpolation.html,
but I think the test is wrong, because it expects background-image
to be transitionable, even though the spec defines it with a discrete
animation type.
* Update web-platform-tests to revision b'50e91f3cfd1140cafc188516488f2dca289239af'
* Delete flaky result for css2/linebox/vertical-align-baseline-002
* Delete flaky result for html/rendering/bindings/the-textarea-element-0/cols-default.html.ini
* Delete flaky result for CSS2/lists/list-style-applies-to-001.xht.ini
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Co-authored-by: Mukilan Thiyagarajan <mukilan@igalia.com>
