Bump web-vitals from 4.2.0 to 4.2.1 in /src (#3695)

Bumps [web-vitals](https://github.com/GoogleChrome/web-vitals) from 4.2.0 to 4.2.1.
- [Changelog](https://github.com/GoogleChrome/web-vitals/blob/main/CHANGELOG.md)
- [Commits](GoogleChrome/web-vitals@v4.2.0...v4.2.1)

---
updated-dependencies:
- dependency-name: web-vitals
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

src/package-lock.json

@@ -47,7 +47,7 @@
     "run-script-os": "1.1.6",
     "showdown": "2.1.0",
     "smartypants": "0.2.2",
-    "web-vitals": "4.2.0",
+    "web-vitals": "4.2.1",
     "xml-js": "1.6.11"
   }
 }