Remediate CDK Warnings

Remediate these warnings (do not ignore)

* installLatestAwsSdk was not specified, and defaults to true. You probably do not want this. Set the global context flag '@aws-cdk/customresources:installLatestAwsSdkDefault' to false to switch this behavior off project-wide, or set the property explicitly to true if you know you need to call APIs that are not in Lambda's built-in SDK version. [ack: @aws-cdk/custom-resources:installLatestAwsSdkNotSpecified]
* AwsSolutions-DDB3: The DynamoDB table does not have Point-in-time Recovery enabled.
* AwsSolutions-EC23: 'AwsSolutions-EC23' threw an error during validation. This is generally caused by a parameter referencing an intrinsic function. You can suppress the "CdkNagValidationFailure" to get rid of this error. For more details enable verbose logging.'

Locate the TypeScript CDK stacks and project context configuration that produce these warnings, then run the CDK synthesis or validation with verbose logging to investigate AwsSolutions-EC23. Done means the installLatestAwsSdk, DynamoDB point-in-time recovery, and EC23 warnings are remediated rather than suppressed.

Written by the indexing model from the issue text.