chore: bump web-ext from 9.3.0 to 9.4.0

Bumps [web-ext](https://github.com/mozilla/web-ext) from 9.3.0 to 9.4.0.
- [Release notes](https://github.com/mozilla/web-ext/releases)
- [Commits](mozilla/web-ext@9.3.0...9.4.0)

---
updated-dependencies:
- dependency-name: web-ext
  dependency-version: 9.4.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package-lock.json

@@ -42,7 +42,7 @@
     "stylelint": "^17.4.0",
     "stylelint-config-standard": "^40.0.0",
     "stylelint-no-unsupported-browser-features": "^8.1.1",
-    "web-ext": "^9.3.0"
+    "web-ext": "^9.4.0"
   },
   "stylelint": {
     "extends": "stylelint-config-standard",