Intermittent timeout in /_webgl/conformance/uniforms/out-of-bounds-uniform-array-access.html

```
  ▶ TIMEOUT [expected OK] /_webgl/conformance/uniforms/out-of-bounds-uniform-array-access.html
  │ 
  │ error: XDG_RUNTIME_DIR not set in the environment.
  └ libEGL warning: No hardware driver found, falling back to software rendering
  ▶ Unexpected subtest result in /_webgl/conformance/uniforms/out-of-bounds-uniform-array-access.html:
  └ NOTRUN [expected PASS] Overall test
```