Nested stack validation incorrect

[jnieman]

If I try to create a nested stack that deploys cross account, the error message should not give a regex stack name validation error message if the stack name matches the valid regex.

1. Create custom construct class PipelineConstruct that creates a codepipeline pipeline.
2. The pipeline should have a stage that contains the CloudFormationCreateReplaceChangeSetAction that deploys to a different account by specifying a different account in the account property of the action.
3. Create stack class that initializes NestedStack and uses the stack class as the scope.
4. Initialize PipelineConstruct and use the initialized nested stack as the scope.
5. run cdk list
6. receive regex stack name validation error message.

public class PipelinesApplication {

    public static void main(final String argv[]) {
        App app = new App();

        new PipelineStack(app, "PipelinesStack", StackProps.builder().env(Consts.Environments.SANDBOX).build());

        app.synth();
    }

    private static class PipelineStack extends Stack {

        public PipelineStack(final App parent, final String id, final StackProps props) {
            super(parent, id, props);

            String projectName = "SomeProject";

            NestedStack nestedStack = new NestedStack(this, projectName + "Stack");
            new PipelineConstruct(nestedStack, projectName + "PipelineProject", projectName);
        }

    }

    private static class PipelineConstruct extends Construct {

        public PipelineConstruct(final Construct scope, final String id, final String projectName) {
            super(scope, id);

            Pipeline pipeline2 = new Pipeline(this, "Pipeline",
                    PipelineProps.builder()
                            .pipelineName(projectName + "Pipeline")
                            .build());

            List<IAction> deployChangeSetActions = new ArrayList<>();
            ArtifactPath artifactPath = ArtifactPath.artifactPath("artifact", "template.yml");

            deployChangeSetActions.add(new CloudFormationCreateReplaceChangeSetAction(
                    CloudFormationCreateReplaceChangeSetActionProps.builder()
                            .actionName("Prepare-Change-Set")
                            .stackName(projectName + "stackName")
                            .changeSetName(projectName + "changeSetName")
                            .adminPermissions(true)
                            .templatePath(artifactPath)
                            .runOrder(3)
                            .account("123456789012")
                            .build()));

            pipeline2.addStage(StageOptions.builder()
                    .stageName("StageName")
                    .actions(deployChangeSetActions)
                    .build());

        }
        
    }

}

Error Log

Exception in thread "main" software.amazon.jsii.JsiiException: Stack name must match the regular expression: /^[A-Za-z][A-Za-z0-9-]*$/, got 'cross-account-support-stack-123456789012' Error: Stack name must match the regular expression: /^[A-Za-z][A-Za-z0-9-]*$/, got 'cross-account-support-stack-123456789012'

Environment

• **CLI Version :**1.16.128
• **Framework Version:**awscdk v1.15.0.DEVPREVIEW
• **OS :**Mac
• **Language :**Java 8

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This is 🐛 Bug Report

[eladb]

Fixed by #4745