Add plausbile to docusaurus (#456)

docs/docusaurus.config.js

@@ -22,6 +22,9 @@ async function createConfig() {
     organizationName: 'Edgeless Systems', // Usually your GitHub org/user name.
     projectName: 'Constellation', // Usually your repo name.
 
+    // plausible
+    scripts: [{ src: 'https://plausible.io/js/plausible.js', async: true, defer: true, 'data-domain': 'docs.edgeless.systems' }],
+
     // Even if you don't use internalization, you can use this field to set useful
     // metadata like html lang. For example, if your site is Chinese, you may want
     // to replace "en" with "zh-Hans".