Add el96 optional sigstore test

Author: ggiguash

test/scenarios-bootc/periodics/el96-crel@optional-sigstore.sh

@@ -0,0 +1,41 @@
+#!/bin/bash
+
+# Sourced from scenario.sh and uses functions defined there.
+
+# Enable container signature verification for current release images,
+# including the optional components.
+# These are ec / rc / z-stream, thus must all to be signed.
+# shellcheck disable=SC2034  # used elsewhere
+IMAGE_SIGSTORE_ENABLED=true
+
+start_image=rhel96-bootc-crel-optionals
+
+scenario_create_vms() {
+    if ! does_image_exist "${start_image}"; then
+        echo "Image '${start_image}' not found - skipping test"
+        return 0
+    fi
+    prepare_kickstart host1 kickstart-bootc.ks.template "${start_image}"
+    launch_vm --boot_blueprint rhel96-bootc
+}
+
+scenario_remove_vms() {
+    if ! does_image_exist "${start_image}"; then
+        echo "Image '${start_image}' not found - skipping test"
+        return 0
+    fi
+	remove_vm host1
+}
+
+scenario_run_tests() {
+    if ! does_image_exist "${start_image}"; then
+        echo "Image '${start_image}' not found - skipping test"
+        return 0
+    fi
+    # Run a minimal test for this scenario as its main functionality is
+    # to verify container image signature check is enabled
+	run_tests host1 \
+        --variable "EXPECTED_OS_VERSION:9.6" \
+        --variable "IMAGE_SIGSTORE_ENABLED:True" \
+        suites/standard1/containers-policy.robot
+}