Disable flaky WebRtcCaptureFromElementBrowserTest on Win.

WebRtcCaptureFromElementBrowserTest.VerifyCanvasCaptureWebGLFrames is
also flaky on Windows, disabling.

Bug: 1335032
Change-Id: I3df2501b6950cfca59e8e9f841e896364757ccdd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3698091


Commit-Queue: Balazs Engedy <engedy@chromium.org>
Owners-Override: Nidhi Jaju <nidhijaju@chromium.org>
Reviewed-by: Nidhi Jaju <nidhijaju@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1012859}