fix(batch): remove default optimal for arm based instance types and add error checks

[1kaileychen]

Issue # (if applicable)

Closes #31148

Reason for this change

When adding an arm-based instance, optimal instance is set by default which consists of an x86-based instance. This causes errors since arm and x86 instances can't be mixed together.

Description of changes

• useOptimalInstanceClasses is set to false for all arm-based instances
• Throws error when trying to mix x86 and arm instances
  • Case 1: Instantiating the class
  • Case 2: addInstanceClass and addInstanceType functions
• Warning useOptimalInstanceClasses is being set to false for arm-based instances

Description of how you validated changes

• Unit test where optimal doesn't get added for arm-based instances
• Unit tests to display errors when instantiating the class
• Unit tests to display errors when addInstanceClass and addInstanceType is adding mixed instances
• Unit tests to display warning for arm based instances

Checklist

• My code adheres to the CONTRIBUTING GUIDE and DESIGN GUIDELINES

---

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

[aws-cdk-automation]

The pull request linter has failed. See the aws-cdk-automation comment below for failure reasons. If you believe this pull request should receive an exemption, please comment and provide a justification.

A comment requesting an exemption should contain the text Exemption Request. Additionally, if clarification is needed add Clarification Request to a comment.

✅ Updated pull request passes all PRLinter validations. Dismissing previous PRLinter review.

[shikha372]

Marking it as do not merge for confirming test changes

[mergify]

Thank you for contributing! Your pull request will be updated from main and then merged automatically (do not update manually, and be sure to allow changes to be pushed to your fork).

[aws-cdk-automation]

AWS CodeBuild CI Report

• CodeBuild project: AutoBuildv2Project1C6BFA3F-wQm2hXv2jqQv
• Commit ID: 43e5c82
• Result: SUCCEEDED
• Build Logs (available for 30 days)

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

[mergify]

Thank you for contributing! Your pull request will be updated from main and then merged automatically (do not update manually, and be sure to allow changes to be pushed to your fork).

[github-actions]

Comments on closed issues and PRs are hard for our team to see.
If you need help, please open a new issue that references this one.