Fix link in CONTRIBUTING.md regarding reactions (#42207)

Co-authored-by: Julien Déramond <juderamond@gmail.com>

Author: coliff

.github/CONTRIBUTING.md

@@ -24,7 +24,7 @@ restrictions:
   respect the opinions of others.
 
 - Please **do not** post comments consisting solely of "+1" or ":thumbsup:".
-  Use [GitHub's "reactions" feature](https://blog.github.com/2016-03-10-add-reactions-to-pull-requests-issues-and-comments/)
+  Use [GitHub's "reactions" feature](https://github.blog/news-insights/product-news/add-reactions-to-pull-requests-issues-and-comments/)
   instead. We reserve the right to delete comments which violate this rule.