Update docs - with the latest version info

[skip ci]

Author: kevin-lee

website/docusaurus.config.js

@@ -115,7 +115,7 @@ const websiteConfig = {
               "path": "v1",
             },
             "current": {
-              "label": "2.0.0-beta20",
+              "label": "2.0.0-beta21",
             },
           }
         },

website/src/pages/versions.js

@@ -23,6 +23,10 @@ function Version() {
   const pastVersions = versions.filter(
     (version) => version !== latestVersion && version.name !== 'current',
   ).concat([
+    {
+      "name": "2.0.0-beta20",
+      "label": "2.0.0-beta20",
+    },
     {
       "name": "2.0.0-beta19",
       "label": "2.0.0-beta19",