build(deps-dev): bump vnu-jar from 21.4.9 to 21.6.11

Bumps [vnu-jar](https://github.com/validator/validator) from 21.4.9 to 21.6.11.
- [Release notes](https://github.com/validator/validator/releases)
- [Changelog](https://github.com/validator/validator/blob/master/CHANGELOG.md)
- [Commits](https://github.com/validator/validator/commits)

---
updated-dependencies:
- dependency-name: vnu-jar
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

package.json

@@ -81,6 +81,6 @@
     "stylelint": "^13.13.1",
     "stylelint-config-twbs-bootstrap": "^2.2.1",
     "tape": "^5.2.2",
-    "vnu-jar": "21.4.9"
+    "vnu-jar": "21.6.11"
   }
 }