feat(cfnspec): cloudformation spec v53.0.0 (#18524)

Co-authored-by: AWS CDK Team <[email protected]>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Author: 3 people

packages/@aws-cdk/cfnspec/CHANGELOG.md

@@ -5,6 +5,12 @@
 * AWS::SageMaker is at 51.0.0
 
 
+## Unapplied changes
+
+* AWS::ECS is at 51.0.0
+* AWS::SageMaker is at 51.0.0
+
+
 ## Unapplied changes
 
 * AWS::ECS is at 51.0.0