using latest Encore version

0.30 to 0.31

Author: TavoNiievez

symfony/webpack-encore-bundle/1.0/package.json

@@ -1,6 +1,6 @@
 {
     "devDependencies": {
-        "@symfony/webpack-encore": "^0.30.0",
+        "@symfony/webpack-encore": "^0.31.0",
         "core-js": "^3.0.0",
         "regenerator-runtime": "^0.13.2",
         "webpack-notifier": "^1.6.0"