[ECS][request]: ECS deployment with rolling update OneAtATime strategy

### Community Note

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**Tell us about your request**
Add in ECS deployment strategy to run one new container at time (Default.OneAtATime)

**Which service(s) is this request for?**
This could be Fargate, ECS (also EKS)

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
As for example, it is possible to do it with the EC2 CodeDeploy that uses a deployment strategy like Default.OneAtATime.
It could be helpful to have it for ECS as well, in case (for example) the containers need to perform database migration at startup and they can't be be fired-up together (or with %Min-Max as they are configurable now) but choose to fire up the container one-by-one (like in CodeDeploy Default.OneAtATime).

**Are you currently working around this issue?**
Implementing the database migration on CodeBuild phase, instead of managing it via software when the containers fire-up.

Start with the request in issue #2229 and review how ECS and Fargate currently handle configurable Min-Max deployment percentages. Compare that behavior with the referenced EC2 CodeDeploy Default.OneAtATime strategy and consider the stated database-migration use case. Done means the ECS deployment strategy requirements and supported scope are defined clearly enough for implementation.

Written by the indexing model from the issue text.