chore(package.json): remove webpack and mocha related dependencies

These dependencies are no longer used and can be removed from the package.json

Author: AtofStryker

package.json

@@ -37,8 +37,6 @@
     "jsdom-global": "^3.0.2",
     "lerna": "^3.20.2",
     "markdown-it-include": "^1.0.0",
-    "mocha": "^5.2.0",
-    "mocha-webpack": "^1.0.1",
     "rollup": "1",
     "rollup-plugin-buble": "^0.19",
     "rollup-plugin-commonjs": "10",
@@ -56,9 +54,7 @@
     "vue-template-compiler": "^2.6.11",
     "vuepress": "^0.14.8",
     "vuepress-theme-vue": "^1.0.3",
-    "vuex": "^3.0.1",
-    "webpack": "^3.0.1",
-    "webpack-node-externals": "^2.5.0"
+    "vuex": "^3.0.1"
   },
   "devDependencies": {
     "@commitlint/cli": "^8.2.0",