fix: add missing MCP fields to vended CDK test spec (#619)

Author: notgitika

src/assets/__tests__/__snapshots__/assets.snapshot.test.ts.snap

@@ -381,6 +381,9 @@ test('AgentCoreStack synthesizes with empty spec', () => {
       evaluators: [],
       onlineEvalConfigs: [],
       policyEngines: [],
+      agentCoreGateways: [],
+      mcpRuntimeTools: [],
+      unassignedTargets: [],
     },
   });
   const template = Template.fromStack(stack);

src/assets/cdk/test/cdk.test.ts

@@ -14,6 +14,9 @@ test('AgentCoreStack synthesizes with empty spec', () => {
       evaluators: [],
       onlineEvalConfigs: [],
       policyEngines: [],
+      agentCoreGateways: [],
+      mcpRuntimeTools: [],
+      unassignedTargets: [],
     },
   });
   const template = Template.fromStack(stack);