feat(stepfunctions-tasks): bedrock createModelCustomizationJob integration (#31913)

This PR was [previously created](#29043) and passed the community review, but the maintainer review stopped midway, and it was eventually closed. There shouldn’t be any issues with the content, so I am submitting the PR again.

### Issue # (if applicable)

Closes #29042

### Reason for this change

AWS stepfunctions support optimized integration with AWS bedrock.
Currently, only invokeModel is supported by CDK, but I would like createModelCustomizationJob to be supported in the same manner.

### Description of changes

I've added CreatemodelCustomizationJob class.

```ts
const taskConfig = {
  baseModel: model,
  clientRequestToken: 'MyToken',
  customizationType: CustomizationType.FINE_TUNING,
  kmsKey,
  customModelName: 'MyCustomModel',
  customModelTags: [{ key: 'key1', value: 'value1' }],
  hyperParameters: {
    batchSize: '10',
  },
  jobName: 'MyCustomizationJob',
  jobTags: [{ key: 'key2', value: 'value2' }],
  outputDataS3Uri: outputBucket.s3UrlForObject(),
  trainingDataS3Uri: trainingBucket.s3UrlForObject(),
  validationDataS3Uri: [validationBucket.s3UrlForObject()],
  vpcConfig: {
    securityGroups: [new ec2.SecurityGroup(stack, 'SecurityGroup', { vpc })],
    subnets: vpc.isolatedSubnets,
  },
};

const task1 = new BedrockCreateModelCustomizationJob(stack, 'CreateModelCustomizationJob1', taskConfig);

const chain = sfn.Chain
  .start(new sfn.Pass(stack, 'Start'))
  .next(task1)
  .next(new sfn.Pass(stack, 'Done'));

new sfn.StateMachine(stack, 'StateMachine', {
  definitionBody: sfn.DefinitionBody.fromChainable(chain),
  timeout: cdk.Duration.seconds(30),
});
```

### Description of how you validated changes

I've added both unit and integ tests.

### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

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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*

Author: badmintoncryer