Bump less from 4.2.0 to 4.2.1 (#22893)

Bumps [less](https://github.com/less/less.js) from 4.2.0 to 4.2.1.
- [Release notes](https://github.com/less/less.js/releases)
- [Changelog](https://github.com/less/less.js/blob/master/CHANGELOG.md)
- [Commits](https://github.com/less/less.js/commits)

---
updated-dependencies:
- dependency-name: less
  dependency-type: direct:production
  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>

package.json

@@ -17,7 +17,7 @@
     "jquery.browser": "0.1.0",
     "jquery.cookie": "1.4.1",
     "jszip": "3.10.1",
-    "less": "4.2.0",
+    "less": "4.2.1",
     "netmask": "2.0.2",
     "source-map": "0.7.4",
     "timeago": "1.6.7",