Update dependency webpack to v4.30.0

package.json

@@ -10,7 +10,7 @@
     },
     "devDependencies": {
         "sass": "1.18.0",
-        "webpack": "4.29.6",
+        "webpack": "4.30.0",
         "webpack-cli": "3.3.0"
     }
 }