Add '/to/doc-comment-references' tooling redirect to page

Author: parlough

firebase.json

@@ -283,6 +283,7 @@
       { "source": "/support/faq", "destination": "/resources/faq", "type": 301 },
       { "source": "/support{,/**}", "destination": "/community", "type": 301 },
 
+      { "source": "/to/doc-comment-references", "destination": "/tools/doc-comments/references", "type": 301 },
       { "source": "/to/enforce-lockfile", "destination": "/guides/packages#get-dependencies-for-production", "type": 301 },
       { "source": "/to/main-function", "destination": "/language/functions#main", "type": 301 },
       { "source": "/to/web-debug-extension", "destination": "https://chromewebstore.google.com/detail/dart-debug-extension/eljbmlghnomdjgdjmbdekegdkbabckhm", "type": 301 },