Ec2 Image Builder: missing OU and KMS options in CFN

### Name of the resource

AWS::ImageBuilder::DistributionConfiguration

### Resource name

_No response_

### Description

Scope of request: CFN template for the Ec2 Image Builder distribution should support OU and KMS options.

Description: The CFN template for EC2 image builder distribution doesn't support the options to add the KMS key and the OU during the distribution of an AMI.
The property _AmiDistributionConfiguration_ allows to specify only UserGroups and UserIds but there's no option for OU and the KMS key to use.

Expected behaviour: CFN template should provide the option to specify OU and KMS.

Ref: https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-imagebuilder-distributionconfiguration.html

### Other Details

_No response_

Start with the AWS::ImageBuilder::DistributionConfiguration documentation linked in the issue and inspect the current AmiDistributionConfiguration coverage. Confirm how OU and KMS options are represented, then consider the work complete when the CloudFormation template can specify both options for EC2 Image Builder AMI distribution.

Written by the indexing model from the issue text.