Merge pull request #863 from owncloud/dependabot/npm_and_yarn/autoprefixer-10.4.21

chore(deps-dev): bump autoprefixer from 10.4.20 to 10.4.21

Author: phil-davis

package-lock.json

@@ -61,7 +61,7 @@
   },
   "devDependencies": {
     "@ronilaukkarinen/gulp-stylelint": "^14.1.2",
-    "autoprefixer": "^10.4.20",
+    "autoprefixer": "^10.4.21",
     "browserify": "^17.0.1",
     "chokidar": "^4.0.3",
     "cssnano": "^7.0.6",