Remove stale WebGL 2 expectations

Autogenerated CL from running:

//content/test/gpu/unexpected_pass_finder.py --project chrome-unexpected-pass-data --include-internal-builders --remove-stale-expectations --narrow-semi-stale-expectation-scope --num-samples 200 --suite webgl2_conformance --jobs 4

Affected bugs for CL description:

R=rubber-stamper@appspot.gserviceaccount.com

Bug: 1403824
Change-Id: I14ff115f9a1818c7ae72032572eac7985cd4a602
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4242009
Auto-Submit: chrome-automated-expectation@chops-service-accounts.iam.gserviceaccount.com <chrome-automated-expectation@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#1104281}

content/test/gpu/gpu_tests/test_expectations/webgl2_conformance_expectations.txt

@@ -554,7 +554,6 @@ crbug.com/982292 [ mac nvidia angle-opengl passthrough ] deqp/functional/gles3/i
 
 ## Mac ASAN ##
 
-crbug.com/1403824 [ mac asan passthrough ] deqp/functional/gles3/vertexarrays/single_attribute.first.html [ RetryOnFailure ]
 
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 # Linux failures   #