[EKS][DNS] [request]: Improvements to the external-dns project

### Community Note

* Please vote on this issue by adding a 👍 [reaction](https://blog.github.com/2016-03-10-add-reactions-to-pull-requests-issues-and-comments/) to the original issue to help the community and maintainers prioritize this request
* Please do not leave "+1" or "me too" comments, they generate extra noise for issue followers and do not help prioritize the request
* If you are interested in working on this issue or have submitted a pull request, please leave a comment

**Tell us about your request**

In order to create a seemless EKS experience, open source contributions to the [external-dns](https://github.com/kubernetes-sigs/external-dns) project are sorely needed.

Currently external-dns works on a polling basis. This leads to your route53 requests being rate limited by amazon if you set the poll interval too short. If you set the poll interval too long then there can be a long delay when it comes to synchronizing ingress changes.

Instead of working on a polling basis, which hammers AWS's services, and leads to a poor customer experience, the project could be enhanced to be event driven for its route53 integration, and to integrate with eventbridge.

Amazon would save a lot of money by reducing load on their route53 service, and it would create a better experience for people running workloads in EKS.

external-dns is a key building block of the EKS experience, its very difficult to have a functional kubernetes cluster without it, and most customers will be installing it. Especially once it's a plugin (its not yet but I already know its on the roadmap to add more plugins).

**Which service(s) is this request for?**
EKS

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**

I'm trying to improve the out of the box EKS experience. Make it so that its easier to get a EKS cluster functional, while avoiding the landmines of Route53 rate limiting that everyone runs into when installing a EKS cluster for the first time.

**Are you currently working around this issue?**

We're using a longer polling interval for external-dns, which isn't a good quality of life, but it works. Also we installed external DNS using helm because there's no plugin for it currently. This meant we had to write a lot of extra terraform ourselves before we had a functional EKS cluster.

**Additional context**

If this isn't a good place for AWS to invest in open source then I don't even know what is.

Start by reviewing the external-dns project’s Route53 integration and the AWS EventBridge integration described in the request. The scope is complete when external-dns can respond to relevant DNS changes without relying on short polling intervals, while avoiding Route53 rate limiting; the issue does not name specific files or tests.

Written by the indexing model from the issue text.