Add PR #5 link to release notes

Author: joels-sandbox-app[bot]

release-notes.md

@@ -21,4 +21,5 @@ This release candidate provides smaller distributed files, faster rendering upda
 
 ## Upgrade context
 
-This release candidate introduces no breaking changes. Adopting version `11.0.0-rc.0` provides smaller outputs, rendering updates, improved server rendered content handling, and compatibility fixes.
+This release candidate introduces no breaking changes. Adopting version `11.0.0-rc.0` provides smaller outputs, rendering updates, improved server rendered content handling, and compatibility fixes.
+See [PR #5](https://github.com/joels-sandgarden/preact/pull/5) for the changes included in this release candidate.