Update dependency webpack-cli to v6 (#56)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

vue-2-webpack/package.json

@@ -19,7 +19,7 @@
     "vue-loader": "15.10.1",
     "vue-template-compiler": "2.7.14",
     "webpack": "5.88.2",
-    "webpack-cli": "5.1.4",
+    "webpack-cli": "6.0.1",
     "webpack-dev-server": "5.0.4"
   },
   "browserslist": [