Mark animation-worklet/idlharness.any.worker.html as flaky

The test is flaky on all platforms.
https://analysis.chromium.org/p/chromium/flake-portal/flakes/occurrences?key=ag9zfmZpbmRpdC1mb3ItbWVyVgsSBUZsYWtlIktjaHJvbWl1bUBibGlua193ZWJfdGVzdHNAZXh0ZXJuYWwvd3B0L2FuaW1hdGlvbi13b3JrbGV0L2lkbGhhcm5lc3MuYW55Lmh0bWwM

Bug: 1045329
Change-Id: I8b324dcf7585408cd8f9867a07a3a31423606643
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2021969Reviewed-by: Xida Chen <xidachen@chromium.org>
Commit-Queue: Yi Gu <yigu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#735381}

third_party/blink/web_tests/TestExpectations

@@ -6450,3 +6450,6 @@ crbug.com/1045510 [ Win7 ] fast/forms/suggestion-picker/date-suggestion-picker-a
 
 # TODO(michaelludwig) - Temporary suppression for Skia change + rebaseline
 crbug.com/1045050 [ Mac ] media/video-layer-crash.html [ Pass Failure ]
+
+crbug.com/1045329 external/wpt/animation-worklet/idlharness.any.worker.html [ Pass Timeout ]
+crbug.com/1045329 virtual/threaded/external/wpt/animation-worklet/idlharness.any.worker.html [ Pass Timeout ]
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