AWS::Redshift::Cluster - Add support for configuring a custom domain

### Name of the resource

AWS::Redshift::Cluster

### Resource name

_No response_

### Description

[The `AWS::Redshift::Cluster` resource](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-redshift-cluster.html) is missing properties for configuring a custom domain on a Redshift cluster.

[Configuring a custom domain](https://docs.aws.amazon.com/redshift/latest/mgmt/connecting-connection-CNAME-create-custom-domain.html) is a useful feature for client convenience (simpler names) and fail-over scenarios (connection re-routing). When enabled, Redshift serves an ACM-issued certificate which can be validated by clients who connect via that domain name.

### Other Details

_No response_

No repository file or test is named. Start by reading the linked AWS::Redshift::Cluster and Redshift custom-domain documentation, then inspect the repository’s existing coverage conventions for this resource; done means the documented custom-domain configuration is represented according to those conventions.

Written by the indexing model from the issue text.