Resolve runtime dependency platform digests

tests/test_runtime_distribution_build.py

@@ -145,6 +145,9 @@ class RuntimeDistributionBuildTests(unittest.TestCase):
 
         self.assertIn('for ARCH in amd64 arm64; do', workflow)
         self.assertIn("tools/checks/runtime-image-smoke.py", workflow)
+        self.assertIn("Resolve managed dependency platform images", workflow)
+        self.assertIn("--postgres-metadata", workflow)
+        self.assertIn("--redis-metadata", workflow)
         self.assertIn("runtime-smoke-amd64.json", workflow)
         self.assertIn("runtime-smoke-arm64.json", workflow)
 
@@ -244,6 +247,15 @@ class RuntimeDistributionBuildTests(unittest.TestCase):
             "registry.example/govoplan/api@sha256:" + "1" * 64,
             metadata["platforms"]["linux/amd64"],
         )
+        dependency_metadata = OCI.resolve_platforms(
+            index,
+            repository="registry.example:5000/library/postgres:16-alpine",
+            index_digest="sha256:" + "a" * 64,
+        )
+        self.assertEqual(
+            "registry.example:5000/library/postgres@sha256:" + "2" * 64,
+            dependency_metadata["platforms"]["linux/arm64"],
+        )
 
         with tempfile.TemporaryDirectory(prefix="govoplan-runtime-finalize-") as value:
             root = Path(value)