tests: drop unused Trustee postgresql dependency in KBS deploy

CI doesn't yet enable bundled Postgres for the Trustee Helm chart, but
Helm still tried to pull the Bitnami subchart from Docker Hub OCI during
dependency build, hitting unauthenticated rate limits on shared runners.

Once we switch to using Postgres in the tests, we will need to drop this
workaround and revisit this issue.

Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>

tests/integration/kubernetes/confidential_kbs.sh

@@ -360,6 +360,28 @@ function kbs_k8s_delete() {
 	kubectl delete ns "${KBS_NS}" --ignore-not-found --wait=false
 }
 
+# Drop optional Trustee subchart dependencies that kata CI never enables.
+#
+# The upstream chart pins postgresql to Bitnami's Docker Hub OCI registry. Helm
+# still requires `helm dependency build` even when postgresql.enabled=false.
+# Our tests always use LocalFs/Memory storage, so remove the unused dependency
+# and skip any remote chart fetch entirely.
+#
+# Parameters:
+#	$1 - Trustee Helm chart directory
+#
+strip_trustee_unused_chart_dependencies() {
+	local chart_dir=$1
+	local chart_yaml="${chart_dir}/Chart.yaml"
+	local chart_lock="${chart_dir}/Chart.lock"
+
+	[[ -f "${chart_yaml}" ]] || die "Trustee Chart.yaml not found at ${chart_yaml}"
+
+	ensure_yq
+	yq -i 'del(.dependencies)' "${chart_yaml}"
+	rm -f "${chart_lock}"
+}
+
 # Deploy the kbs on Kubernetes via the Trustee Helm chart.
 #
 # Parameters:
@@ -555,10 +577,10 @@ function kbs_k8s_deploy() {
 	fi
 
 	# The chart declares a (condition-gated, disabled-by-default) postgresql
-	# dependency, which helm still requires to be present under charts/ before
-	# install. Fetch it from the versions pinned in the chart's Chart.lock.
-	echo "::group::Build Helm chart dependencies"
-	helm dependency build "${COCO_HELM_CHART_DIR}"
+	# dependency pinned to Docker Hub OCI. CI never enables bundled Postgres, so
+	# drop the dependency and avoid `helm dependency build` entirely.
+	echo "::group::Prepare Trustee Helm chart"
+	strip_trustee_unused_chart_dependencies "${COCO_HELM_CHART_DIR}"
 	echo "::endgroup::"
 
 	echo "::group::Deploy Trustee via Helm"