docs(batch): add note on update fatgate compute environment (#34022)

…ments

### Issue #34008

Closes [#34008](#34008).

### Reason for this change

### Describe the issue

[aws-cdk-lib.aws_batch.FargateComputeEnvironment](https://docs.aws.amazon.com/cdk/api/v2/docs/aws-cdk-lib.aws_batch.FargateComputeEnvironment.html) needs to be updated for Fargate CEs

This doc is not consistent with other docs:

https://docs.aws.amazon.com/batch/latest/userguide/updating-compute-environments.html
https://docs.aws.amazon.com/cli/latest/reference/batch/update-compute-environment.html

Following fields in `FargateComputeEnvironmentProps` of `FargateComputeEnvironment` are not applicable. We might not be able to change model now as it is out, we can update documentation to reflect it is not applicable.

All these params are optional `?` .
```
replaceComputeEnvironment?
terminateOnUpdate?
updateTimeout?
updateToLatestImageVersion?
```
### Links

https://github.com/aws/aws-cdk/blob/main/packages/aws-cdk-lib/aws-batch/README.md

### Description of changes

Update README, following the instructions in the issue.

### Describe any new or updated permissions being added

No.


### Description of how you validated changes

No, only README change.

### 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)

----

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

Author: deftcx-aws

packages/aws-cdk-lib/aws-batch/README.md

@@ -50,6 +50,8 @@ and only applies to `ManagedEc2EcsComputeEnvironment`s.
 The following code configures a Compute Environment to only use spot instances that
 are at most 20% the price of the on-demand instance price:
 
+_Note_: For `FargateComputeEnvironment`, while the `FargateComputeEnvironmentProps` interface includes properties like `replaceComputeEnvironment`, `terminateOnUpdate`, `updateTimeout`, and `updateToLatestImageVersion`, these specific properties are **not applicable** when configuring AWS Batch Fargate compute environments. They primarily apply to EC2-based compute environments. Please refer to the official [AWS Batch UpdateComputeEnvironment API documentation](https://docs.aws.amazon.com/batch/latest/APIReference/API_UpdateComputeEnvironment.html) and [User Guide](https://docs.aws.amazon.com/batch/latest/userguide/updating-compute-environments.html) for details on updating Fargate compute environments.
+
 ```ts
 const vpc = new ec2.Vpc(this, 'VPC');
 new batch.ManagedEc2EcsComputeEnvironment(this, 'myEc2ComputeEnv', {