Update dependency del to v4.1.0 (#442)

Author: renovate[bot]

package-lock.json

@@ -39,7 +39,7 @@
   "devDependencies": {
     "chalk": "2.4.2",
     "chromedriver": "2.46.0",
-    "del": "4.0.0",
+    "del": "4.1.0",
     "eslint": "5.16.0",
     "eslint-config-airbnb": "17.1.0",
     "eslint-plugin-import": "2.16.0",