Merge pull request #13780 from rabbitmq/mergify/bp/v4.1.x/pr-13779

GitHub Actions: Use RabbitMQ 4.0.9 for mixed-version testing (backport #13779)

Author: dumbbell

.github/workflows/test-make-target.yaml

@@ -57,7 +57,7 @@ jobs:
       uses: dsaltares/fetch-gh-release-asset@master
       if: inputs.mixed_clusters
       with:
-        version: 'tags/v4.0.5'
+        version: 'tags/v4.0.9'
         regex: true
         file: "rabbitmq-server-generic-unix-\\d.+\\.tar\\.xz"
         target: ./