feat(ec2): support `instanceInitiatedShutdownBehavior` for EC2 instance

[badmintoncryer]

Issue # (if applicable)

Closes #30164

Reason for this change

Cloudformation supports to specify instanceInitiatedShutdownBehavior but CDK cannot.

Description of changes

Add instanceInitiatedShutdownBehavior to InstanceProps.

Description of how you validated changes

Add both unit and integ tests.

Checklist

• [x] My code adheres to the CONTRIBUTING GUIDE and DESIGN GUIDELINES

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

[aws-cdk-automation]

AWS CodeBuild CI Report

• CodeBuild project: AutoBuildv2Project1C6BFA3F-wQm2hXv2jqQv
• Commit ID: 630481f301f574e85827131d0326fced0d40a08d
• Result: SUCCEEDED
• Build Logs (available for 30 days)

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[badmintoncryer]

@go-to-k Thank you for your review! I replied to your comment.

[badmintoncryer]

Thanks always!

[aws-cdk-automation]

AWS CodeBuild CI Report

• CodeBuild project: AutoBuildv2Project1C6BFA3F-wQm2hXv2jqQv
• Commit ID: 5f4ce774b7c0afc2b954dc3b321c8e8198f986b9
• Result: SUCCEEDED
• Build Logs (available for 30 days)

Powered by github-codebuild-logs, available on the AWS Serverless Application Repository

[mergify[bot]]

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