support settings.oci-defaults on ecs variants

[webern]

What I'd like:

In #2697 we added settings support for setting OCI defaults in orchestrator-launched pods (see also #1703 #2404). The settings we added for this are:

• settings.oci-defaults.resource-limits
• settings.oci-defaults.capabilities

We want these settings to be available and work the same way on ECS variants. The ECS variants use Docker, so the implementation for these Bottlerocket settings may be non-trivial.

Here are a couple of relevant links:

• rlimits might be simple: https://github.com/moby/moby/blob/dd61302f5bd87c887ec4cba22479a37ef78914c8/daemon/oci_linux.go#L40
• Capabilities is more involved because we would need a patch to read capabilities from a file instead of using this hardcoded list: https://github.com/moby/moby/blob/dd61302f5bd87c887ec4cba22479a37ef78914c8/daemon/oci_linux.go#L40

Any alternatives you've considered:

N/A