Intermittent ERROR in `/html/semantics/scripting-1/the-script-element/module/import-meta/import-meta-url.html`

https://github.com/servo/servo/actions/runs/19578653450/job/56071228522

```
   ▶ ERROR [expected OK] /html/semantics/scripting-1/the-script-element/module/import-meta/import-meta-url.html
  │   → import.meta may only appear in a module
  │ 
  └ http://web-platform.test:8000/html/semantics/scripting-1/the-script-element/module/import-meta/postmessage-worker.js?DedicatedWorker:3:22
```