fix: npm audit vulnerability (close: #493)(#641)

Author: cuyl

package.json

@@ -67,10 +67,10 @@
     "lodash.throttle": "^4.1.1",
     "lru-cache": "^4.1.2",
     "markdown-it": "^8.4.1",
-    "markdown-it-anchor": "^4.0.0",
+    "markdown-it-anchor": "^5.0.2",
     "markdown-it-container": "^2.0.0",
     "markdown-it-emoji": "^1.4.0",
-    "markdown-it-table-of-contents": "^0.3.3",
+    "markdown-it-table-of-contents": "^0.4.0",
     "mini-css-extract-plugin": "^0.4.1",
     "nprogress": "^0.2.0",
     "optimize-css-assets-webpack-plugin": "^4.0.0",