[Gstreamer] tests media/track/in-band/track-in-band-*-added-once.html are flaky

[Arcady Goldmints-Orlov]

The flakiness has gotten substantially worse since r281741 but they were occasionally failing even before that, so I don't want to necessarily call this a regression.

When these tests fail, it looks like this:
--- /home/buildbot/worker/gtk-linux-64-release-tests/build/layout-test-results/media/track/in-band/track-in-band-kate-ogg-cues-added-once-expected.txt
+++ /home/buildbot/worker/gtk-linux-64-release-tests/build/layout-test-results/media/track/in-band/track-in-band-kate-ogg-cues-added-once-actual.txt
@@ -6,13 +6,13 @@
 ** Setting track 1 to showing
 RUN(inbandTrack1.mode = 'showing')
 RUN(video.play())
-EXPECTED (inbandTrack1.cues.length > '0') OK
+EXPECTED (inbandTrack1.cues.length > '0'), OBSERVED '0' FAIL
 RUN(video.pause())
 RUN(video.currentTime = 0)
 RUN(video.play())
 
 EVENT(seeked)
-EXPECTED (inbandTrack1.cues.length > '0') OK
+EXPECTED (inbandTrack1.cues.length > '0'), OBSERVED '0' FAIL
 RUN(video.pause())
 Test all cues are equal OK
 END OF TEST

[Arcady Goldmints-Orlov]

Created attachment 437441 [details]
Gardening patch

[EWS]

Committed r282070 (241370@main): <https://commits.webkit.org/241370@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 437441 [details].

[Radar WebKit Bug Importer]

<rdar://problem/82802829>

[Arcady Goldmints-Orlov]

Reopening to track the fix.