Update jenkins/ath Docker tag to v6504

renovate[bot] · web-flow · commit d322d02e743a · 2025-12-28T00:56:56.000Z
diff --git a/ath.sh b/ath.sh
@@ -6,7 +6,7 @@ set -o xtrace
 cd "$(dirname "$0")"
 
 # https://github.com/jenkinsci/acceptance-test-harness/releases
-export ATH_VERSION=6483.vecb_7d34edb_75
+export ATH_VERSION=6504.v878e5b_e776d7
 
 if [[ $# -eq 0 ]]; then
 	export JDK=21
