Fix wpt importer by adding another flaky test.

This time it's html/semantics/selectors/pseudo-classes/link.html on Win.
Adding it to the same recent batch since we haven't had a successful import
since those last few flakes were added.

TBR=robertma

Bug: 1049607
Change-Id: Ied06fa405c95249340a77e3984d9fdc61a14f7b1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2043853Reviewed-by: Luke Z <lpz@chromium.org>
Commit-Queue: Luke Z <lpz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#739439}

third_party/blink/web_tests/TestExpectations

@@ -6550,6 +6550,7 @@ crbug.com/1049607 external/wpt/fetch/api/response/response-error-from-stream.htm
 crbug.com/1049607 virtual/omt-worker-fetch/external/wpt/fetch/api/response/response-error-from-stream.html [ Pass Failure ]
 crbug.com/1049607 [ Linux ] external/wpt/js-self-profiling/idlharness.any.html [ Pass Failure ]
 crbug.com/1049607 [ Linux ] external/wpt/js-self-profiling/idlharness.any.worker.html [ Pass Failure ]
+crbug.com/1049607 [ Win ] external/wpt/html/semantics/selectors/pseudo-classes/link.html [ Pass Failure ]
 
 # Sheriff 2020-02-07