enforces CDK-specific linter rules
All linter rules live in rules.ts. To create a new rule, create a new class
in that file that extends ValidationRule. That class will be automatically
picked up by pkglint when it is run.
When designing a new rule, do not assume that pkglint will run on a built
aws-cdk repository. pkglint is sometimes run on just the source code of
aws-cdk modules so validating compiled code will result in failure.