1. Title -> AWS::ECR::Repository - Request to support Force Removal of Non-empty ECR repositories

2. Scope of request -> AWS::ECR::Repository supports deleting an empty ECR repository but doesn't support force deleting a non-empty ECR repository.

3. Expected behavior -> In Delete, it should allow an option to force delete a non-empty ECR repository and delete all Images in the ECR repository.

4. Test case recommendation (optional) -> it should help me delete an ECR repository given a force flag is supplied; it shouldn't delete a non-empty repository if the force flag is not provided.

5. Links to existing API doc (optional) -> https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-ecr-repository.html

6. Category tag (optional) -> Containers

7. Any additional context (optional)

This is needed for CDK to support a removal policy which can force delete a non-empty ECR repository.
aws/aws-cdk#2765
https://docs.aws.amazon.com/cdk/api/latest/docs/aws-ecr-readme.html
https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_core.RemovalPolicy.html