⬆️ Update gulp-autoprefixer

Author: lucasgruwez

package.json

@@ -20,7 +20,7 @@
   "license": "MIT",
   "devDependencies": {
     "gulp": "^3.9.1",
-    "gulp-autoprefixer": "^3.1.1",
+    "gulp-autoprefixer": "^4.0.0",
     "gulp-clean-css": "^3.0.3",
     "gulp-cssbeautify": "^0.1.3",
     "gulp-rename": "^1.2.2",