chore(codepipeline-actions): bump up the solutionStack in the integ test (#28799)

Currently, the solutionStack of Elastic Beanstalk that is specified is out of date, causing integ tests to fail.
```
"No Solution Stack named '64bit Amazon Linux 2023 v6.0.2 running Node.js 18' found. (Service: ElasticBeanstalk, Status Code: 400, Request ID: 625a591c-9bb2-4c7c-9404-cf192fdae9bb)"
```

It may be better in the future that integ-test can always deploy using the latest version using the custom resource.
(It may be difficult to use AwsCustomResource because the size of the `SolutionStacks` (array) property alone is 4KB.)
https://docs.aws.amazon.com/AWSJavaScriptSDK/v3/latest/Package/-aws-sdk-client-elastic-beanstalk/Interface/ListAvailableSolutionStacksResultMessage/

----

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

Author: sakurai-ryo

packages/@aws-cdk-testing/framework-integ/test/aws-codepipeline-actions/test/integ.pipeline-elastic-beanstalk-deploy.js.snapshot/aws-cdk-codepipeline-elastic-beanstalk-deploy.template.json

@@ -441,7 +441,7 @@
       "Value": "AWSServiceRoleForElasticBeanstalkManagedUpdates"
      }
     ],
-    "SolutionStackName": "64bit Amazon Linux 2023 v6.0.2 running Node.js 18"
+    "SolutionStackName": "64bit Amazon Linux 2023 v6.0.4 running Node.js 18"
    },
    "DependsOn": [
     "beastalkapp",

packages/@aws-cdk-testing/framework-integ/test/aws-codepipeline-actions/test/integ.pipeline-elastic-beanstalk-deploy.js.snapshot/manifest.json

@@ -79,7 +79,7 @@ const beanstalkEnv = new elasticbeanstalk.CfnEnvironment(stack, 'beanstlk-env',
   applicationName: beanstalkApp.applicationName!,
   environmentName: 'codepipeline-test-env',
   // see https://docs.aws.amazon.com/elasticbeanstalk/latest/platforms/platforms-supported.html#platforms-supported.nodejs
-  solutionStackName: '64bit Amazon Linux 2023 v6.0.2 running Node.js 18',
+  solutionStackName: '64bit Amazon Linux 2023 v6.0.4 running Node.js 18',
   optionSettings: [
     {
       namespace: 'aws:autoscaling:launchconfiguration',