chore: bump vuepress

Author: yyx990803

Diff for: package.json

@@ -76,7 +76,7 @@
     "vue": "^2.5.16",
     "vue-server-renderer": "^2.5.16",
     "vue-template-compiler": "^2.5.16",
-    "vuepress": "^0.8.4",
+    "vuepress": "^0.9.0",
     "vuepress-theme-vue": "^1.0.0",
     "webpack": "^4.1.0",
     "webpack-cli": "^2.0.10",