fix(aws_route53): cannot use CfnParameter.valueAsNumber for L2 RecordSet weight (#31823)

### Issue # (if applicable)

Closes #31810.

### Reason for this change

Could not use CfnParameter.valueAsNumber for L2 RecordSet weight.

### Description of changes

Adding validation of weight property as a potential Token in RecordSet constructor.

### Description of how you validated changes

Added unit and integration test.

### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

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*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: nicholaschiasson