Bump less from 4.1.3 to 4.2.0 (#40)

Bumps [less](https://github.com/less/less.js) from 4.1.3 to 4.2.0.
- [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:development
  update-type: version-update:semver-minor
...

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

package.json

@@ -4,7 +4,7 @@
   "description": "grunt-ect template",
   "main": "Gruntfile.js",
   "devDependencies": {
-    "less": "^4.1.3",
+    "less": "^4.2.0",
     "grunt": "^1.6.1",
     "grunt-contrib-less": "^3.0.0",
     "grunt-contrib-watch": "^1.1.0",