Suppress webgl-compressed-texture-s3tc flake on Linux Intel.

Observed flaky after starting testing on the passthrough command
decoder on this configuration.

Tbr: geofflang@chromium.org
Bug: 872302
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
Change-Id: I44700af5fa229f10037435c226f870e306736730
No-Try: True
Reviewed-on: https://chromium-review.googlesource.com/1184178
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Commit-Queue: Kenneth Russell <kbr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#584914}
1 file changed