fix(core): cross region ssm writer update

packages/@aws-cdk/core/lib/custom-resource-provider/cross-region-export-providers/cross-region-ssm-writer-handler/index.ts

@@ -30,9 +30,13 @@ export async function handler(event: AWSLambda.CloudFormationCustomResourceEvent
         const removedExports = except(oldExports, exports);
         await throwIfAnyInUse(ssm, removedExports);
         // if the ones we are removing are not in use then delete them
-        await ssm.deleteParameters({
-          Names: Object.keys(removedExports),
-        }).promise();
+        // skip if no export names are to be deleted
+        const removedExportsNames = Object.keys(removedExports);
+        if (removedExportsNames.length > 0) {
+          await ssm.deleteParameters({
+            Names: removedExportsNames,
+          }).promise();
+        }
 
         // also throw an error if we are creating a new export that already exists for some reason
         await throwIfAnyInUse(ssm, newExports);

packages/@aws-cdk/core/test/custom-resource-provider/cross-region-ssm-writer-handler.test.ts

@@ -177,6 +177,7 @@ describe('cross-region-ssm-writer entrypoint', () => {
       });
       expect(mockPutParameter).toHaveBeenCalledTimes(1);
       expect(mocklistTagsForResource).toHaveBeenCalledTimes(1);
+      expect(mockDeleteParameters).toHaveBeenCalledTimes(0);
     });
 
     test('removed exports are deleted', async () => {