chore: add html-webpack-plugin to devDependencies

Author: haoqunjiang

package.json

@@ -39,6 +39,7 @@
   "devDependencies": {
     "eslint": "^4.19.1",
     "eslint-plugin-vue-libs": "^2.1.0",
+    "html-webpack-plugin": "^3.2.0",
     "jasmine": "^3.1.0",
     "jsdom": "^11.9.0",
     "memory-fs": "^0.4.1",