fix(amplify): unable to re-run integ test due to missing status field in customRule (#33973)

### Issue # (if applicable)

N/A

I found this problem while working on #33962.

### Reason for this change
Re-running `packages/@aws-cdk/aws-amplify-alpha/test/integ.app.ts`, got the following error:

```sh
Resource handler returned message: "Invalid request provided: Status field in rewrite custom rules should not be empty (Service: Amplify, Status Code: 400, Request ID: 3f3694f1-3eeb-4af3-8cdf-8b77b6387e57) (SDK Attempt Count: 1)" (RequestToken: 5748aef8-c0e1-1a1d-ab27-1bab938e0bd3, HandlerErrorCode: InvalidRequest)
```

If `status` is omitted in `customRules`, `App` cannot be deployed.



### Description of changes
Specify `status` property in integ test.



### Describe any new or updated permissions being added
N/A




### Description of how you validated changes
Re-ran integ test.



### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: mazyu36

packages/@aws-cdk/aws-amplify-alpha/test/integ.app.js.snapshot/cdk-amplify-app.assets.json

@@ -70,6 +70,7 @@
     "CustomRules": [
      {
       "Source": "/source",
+      "Status": "301",
       "Target": "/target"
      }
     ],