chore(package): update gulp-less to version 4.0.0

Author: greenkeeper[bot]

package.json

@@ -68,7 +68,7 @@
     "gulp-if": "^2.0.1",
     "gulp-imagemin": "^4.0.0",
     "gulp-install": "^1.1.0",
-    "gulp-less": "^3.3.2",
+    "gulp-less": "^4.0.0",
     "gulp-main-npm-files": "^1.0.5",
     "gulp-plumber": "^1.1.0",
     "gulp-pretty-data": "^0.2.0",