Consuming app production build might break

**Describe the bug**
For some apps with certain configuration, the app build might break and throw the following error message, which seems to come from the integration of the `closest` polyfill.
```
ENOENT: no such file or directory, open '/tmp/broccoli-2150353w3la8rlV2V/out-15299-broccoli_debug_debug_374_vendor_js/vendor/polyfills/closest.js'
```

**To Reproduce**
Not always reproducible, only on certain apps.

**Expected behavior**
App should build successfully.

**Screenshots**

**Additional context**
For now, we don't `import` the `closest` polyfill if the `path` can not be found to mitigate the issue. Apps affected by this would need to apply their own `closest` polyfill on their `app`.