Merge pull request #10024 from rabbitmq/mergify/bp/v3.12.x/pr-10023

GitHub Actions: Convert '_' to '-' in `$AWS_ECS_CLUSTER_NAME` (backport #10023)

Author: michaelklishin

.github/workflows/rabbitmq_peer_discovery_aws.yaml

@@ -54,5 +54,5 @@ jobs:
           --test_env AWS_ACCESS_KEY_ID=${{ secrets.CONCOURSE_AWS_ACCESS_KEY_ID }} \
           --test_env AWS_SECRET_ACCESS_KEY=${{ secrets.CONCOURSE_AWS_SECRET_ACCESS_KEY }} \
           --test_env RABBITMQ_IMAGE="pivotalrabbitmq/rabbitmq:${{ github.sha }}-otp-max-bazel" \
-          --test_env AWS_ECS_CLUSTER_NAME="rabbitmq-peer-discovery-aws-actions-${branch_or_tag//./-}" \
+          --test_env AWS_ECS_CLUSTER_NAME="rabbitmq-peer-discovery-aws-actions-${branch_or_tag//[._]/-}" \
           --verbose_failures