Ignore 8.x branch in staging DRA jobs

(cherry picked from commit 61e09d3)

Author: mark-vieira

.buildkite/dra-release.sh

@@ -4,7 +4,7 @@ set -euo pipefail
 
 DRA_WORKFLOW=${DRA_WORKFLOW:-snapshot}
 
-if [[ "$BUILDKITE_BRANCH" == "main" && "$DRA_WORKFLOW" == "staging" ]]; then
+if [[ ("$BUILDKITE_BRANCH" == "main" || "$BUILDKITE_BRANCH" == *.x) && "$DRA_WORKFLOW" == "staging" ]]; then
 	exit 0
 fi