chore: include RELEASE_NOTES in packed distribution (backport #17118) (…

…#17119)

This is an automatic backport of pull request #17118 done by [Mergify](https://mergify.io).


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pack.sh

@@ -92,8 +92,9 @@ cat > ${distdir}/build.json <<HERE
 }
 HERE
 
-# copy CHANGELOG.md to dist/ for github releases
+# copy CHANGELOG.md and RELEASE_NOTES.md to dist/ for github releases
 cp ${changelog_file} ${distdir}/CHANGELOG.md
+cp RELEASE_NOTES.md ${distdir}/RELEASE_NOTES.md
 
 # defensive: make sure our artifacts don't use the version marker (this means
 # that "pack" will always fails when building in a dev environment)