feat(aws-autoscaling): allow setting spotPrice

[SoManyHs]

Fixes #2208.

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Pull Request Checklist

• Testing
  • Unit test added (prefer not to modify an existing test, otherwise, it's probably a breaking change)
  • CLI change?: coordinate update of integration tests with team
  • cdk-init template change?: coordinated update of integration tests with team
• Docs
  • jsdocs: All public APIs documented
  • README: README and/or documentation topic updated
  • Design: For significant features, design document added to design folder
• Title and Description
  • Change type: title prefixed with fix, feat and module name in parens, which will appear in changelog
  • Title: use lower-case and doesn't end with a period
  • Breaking?: last paragraph: "BREAKING CHANGE: <describe what changed + link for details>"
  • Issues: Indicate issues fixed via: "Fixes #xxx" or "Closes #xxx"
• Sensitive Modules (requires 2 PR approvers)
  • IAM Policy Document (in @aws-cdk/aws-iam)
  • EC2 Security Groups and ACLs (in @aws-cdk/aws-ec2)
  • Grant APIs (only if not based on official documentation with a reference)

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[SoManyHs]

Note: Is it worth refactoring instanceType to be in the CommonAutoScalingGroupProps, since it's used in the three places that extend that interface? (EKS cluster, ECS cluster, and regular ASG).

[piradeepk]

LGTM!

[piradeepk]

Note: Is it worth refactoring instanceType to be in the CommonAutoScalingGroupProps, since it's used in the three places that extend that interface? (EKS cluster, ECS cluster, and regular ASG).

I think it makes sense to refactor instanceType into CommonAutoScalingGroupProps. Currently, every props that extends CommonAutoScalingGroupProps has instanceType as a property.

Question: Should SpotPrice also be present in all 3 places (EKS cluster, ECS cluster, and regular ASG)., and if so, it would make sense to refactor that as well.

[SoManyHs]

From talking offline with @rix0rrr:
The common properties are all optional on purposes, so you can always safely extend them to add more customization without restricting the rest of your api.

since instanceType is a required property, it wouldn't make sense to add them to the common props on that basis. However, perhaps another extendable interface with required properties would be useful and maybe can be done in a future PR.

[piradeepk]

Makes sense, thanks!