chore(sidebar): Add link to base.org/stats (#1599)

Author: wbnns

apps/base-docs/sidebars.js

@@ -93,6 +93,11 @@ module.exports = {
       collapsed: false,
       items: ['security/bounty', 'security/report', 'security/app-blocklist'],
     },
+    {
+      type: 'link',
+      label: 'Metrics',
+      href: 'https://base.org/stats',
+    },
     {
       type: 'link',
       label: 'Status',