fix(ecs): stack name can result in noncompliant capacity provider name

[kichik]

Previously fixed with #29235 but only for lower case stack names. The error could still be reproduced with stack names starting with Ecs or AWS, etc.

Issue # (if applicable)

Closes #29151

Reason for this change

const app = new cdk.App();
const stack = new cdk.Stack(app, 'EcsCp');
const vpc = new ec2.Vpc(stack, 'Vpc');
const cluster = new ecs.Cluster(stack, 'EcsCluster');

const autoScalingGroupAl2 = new autoscaling.AutoScalingGroup(stack, 'asgal2', {
  vpc,
  instanceType: new ec2.InstanceType('bogus'),
  machineImage: ecs.EcsOptimizedImage.amazonLinux2(),
});

const capacityProvider = new ecs.AsgCapacityProvider(stack, 'provideral2-2', {
    autoScalingGroup: autoScalingGroupAl2,
    enableManagedTerminationProtection: false,
});

Deploying the code above will result in:

Resource handler returned message: "Invalid request provided: CreateCapacityProvider error: The specified capacity provider name is invalid. Up to 255 characters are allowed, including letters (upper and lowercase), numbers, underscores, and hyphens. The name cannot be prefixed with "aws", "ecs", or "fargate". Specify a valid name and try again. (Service: Ecs, Status Code: 400, Request ID: 6c28bb07-463b-497a-9e18-046f8ef58de0) (SDK Attempt Count: 1)" (RequestToken: 2e19581f-7343-6fda-588e-94cbe50066d1, HandlerErrorCode: InvalidRequest)

Description of changes

The regular expression testing for "bad" prefixes was adjusted to be case-insensitive.

Describe any new or updated permissions being added

No new permissions.

Description of how you validated changes

Unit tests were updated to confirm the issue and then the code was fixed and the new unit test passed.

Checklist

• 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]

The pull request linter fails with the following errors:

❌ Fixes must contain a change to an integration test file and the resulting snapshot.

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.

✅ A exemption request has been requested. Please wait for a maintainer's review.

[kichik]

Exemption Request: There is already an integration test for capacity provider. The unit test should suffice here.