Fix invalid CSS state web platform tests

[keithamus]

f91046e

Fix invalid CSS state web platform tests
https://bugs.webkit.org/show_bug.cgi?id=266822

Reviewed by Tim Nguyen.

Due to specificity of the :has() selector overriding the sibling
selector, the sibling selector test was never valid. Adding `[id]` to
the sibling selector bumps the specificity high enough to override the
`:has` style rule so that the sibling selector style rule can take
precedence, leading to a valid test.

Additionally, the `:has` style rule rendering the red colour meant that the
`:has` test was also always invalid. Changing the stylerule to use a
cyan (#0ff) helps differentiate the test. The actual test checked to see
if the colour was blue, which is obviously incorrect and this has now
  also been changed to assert that it should be the same teal as applied
  in the style rule.

* LayoutTests/imported/w3c/web-platform-tests/custom-state-pseudo-class/state-css-selector.tentative-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/custom-state-pseudo-class/state-css-selector.tentative.html:

Canonical link: https://commits.webkit.org/272465@main

3d5c5ca

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	🧪 wpe-wk2
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	✅ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🛠 gtk
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 api-gtk
	✅ 🛠 tv-sim	✅ 🧪 mac-wk2-stress
✅ 🛠 🧪 merge	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on current version of this PR (hash 3d5c5ca)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	🧪 wpe-wk2
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	✅ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🛠 gtk
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 api-gtk
	✅ 🛠 tv-sim	✅ 🧪 mac-wk2-stress
✅ 🛠 🧪 merge	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-commit-queue]

Committed 272465@main (f91046e): https://commits.webkit.org/272465@main

Reviewed commits have been landed. Closing PR #22208 and removing active labels.