Update _redirects

Author: ryanfoxtyler

public/_redirects

@@ -3,3 +3,6 @@
 
 /docs/dgraphcloud/*    /docs/cloud/:splat 301!
 /docs/v21.03/*         https://release-v21-03--dgraph-docs-repo.netlify.app/docs/v21.03/:splat 200!
+/docs/v22.0/*          https://release-v22-0--dgraph-docs-repo.netlify.app/docs/v21.03/:splat 200!
+/docs/v23.0/*          https://release-v23-0--dgraph-docs-repo.netlify.app/docs/v21.03/:splat 200!
+/docs/v23.1/*          https://release-v23-1--dgraph-docs-repo.netlify.app/docs/v21.03/:splat 200!