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 300 --suite webgl2_conformance --jobs 4

Affected bugs for CL description:

R=rubber-stamper@appspot.gserviceaccount.com

Bug: 1240443, 1426916
Change-Id: I9dfd59ecb73fc4dd63c20468c203f1b5c1dc8a9c
Fixed: 1037650, 1382796
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4547015
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
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>
Cr-Commit-Position: refs/heads/main@{#1146410}