[ECR] [request]: Support containers.sentinelone.net with Pull Through Cache

### Community Note

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**Tell us about your request**
What do you want us to build?

We would like to use `Pull Through Cache` with [containers.sentinelone.net](http://containers.sentinelone.net/).

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

Elastic Container Registry

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
What outcome are you trying to achieve, ultimately, and why is it hard/impossible to do right now? What is the impact of not having this problem solved? The more details you can provide, the better we'll be able to understand and solve the problem.

Using a `Private Pull Through Cache` would mean we would not have to build the containers, or manage manifests for different architectures. While you can pull from Sentinel One directly we would like to use ECR for vendoring, caching, reducing the need to manage secrets.

**Are you currently working around this issue?**
How are you currently solving this problem?

As we can not currently use [containers.sentinelone.net](http://containers.sentinelone.net/) as Private Pull Through Cache. We copy the Containers from Sentinel One and push them into our own Elastic Container Repository.

**Additional context**
Anything else we should know?

N/A

**Attachments**
If you think you might have additional information that you'd like to include via an attachment, please do - we'll take a look. (Remember to remove any personally-identifiable information.)

N/A

No repository files, tests, or implementation entry points are identified. Start by determining where ECR Pull Through Cache provider support is tracked; done would mean supporting containers.sentinelone.net as a private cache without requiring manual image copying.

Written by the indexing model from the issue text.