improve: 添加contextPath环境变量，以利于生产环境部署

.roadhogrc.js

@@ -24,7 +24,6 @@ module.exports = {
     'menu-dark-bg': '#404040',
     "layout-header-padding": "0",
   },
-  publicPath: "/bg",
   define: {
     contextPath: "bg"
   },