Be able to get Amplify project DNSSEC compliant

### Before opening, please confirm:

- [X] I have checked to see if my question is addressed in the [FAQ](https://github.com/aws-amplify/amplify-hosting/blob/master/FAQ.md).
- [X] I have [searched for duplicate or closed issues](https://github.com/aws-amplify/amplify-hosting/issues?q=is%3Aissue+).
- [X] I have removed any sensitive information from my code snippets and submission.

### Amplify Hosting feature

Frontend builds

### Is your feature request related to a problem? Please describe:

We're hosting our React front-end application using AWS Amplify. We use a custom (sub)domain, which resolves and works from the browser.

However we noticed that the subdomain has DNSSEC issues and it seems impossible for us to solve this. We do not manage the cloudfront distribution that is being created by Amplify and cannot change anything for this domain.

### Describe how you'd like this feature to work

We would like to see a way to solve the DNSSEC issues

Start by reviewing Amplify Hosting's custom-domain flow and how its managed CloudFront distribution handles the reported subdomain. Determine what DNSSEC capability or configuration is missing, and consider the issue complete only when a documented way to make an Amplify-hosted custom domain DNSSEC compliant is available.

Written by the indexing model from the issue text.