[ECR] [request]: Force update for ECR pull through cache

### Community Note

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**Tell us about your request**

It'd be great to be able to force ECR pull through cache to update even before the 24-hours period passes.

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

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
It would allow using just ECS force redeployment for deploying new `:latest` tag. Now you have to use specific tags and that results in creating new ECS task version for every deploy.

**Are you currently working around this issue?**
Not using pull through cache (yet).

Start by reviewing the ECR pull-through cache behavior described in the issue, especially the 24-hour refresh period, and how ECS force redeployment handles the :latest tag. Done means a cache refresh can be forced before 24 hours so redeployment can use the updated image without creating a new ECS task version.

Written by the indexing model from the issue text.