[confmap] Add converter and provider settings to confmap.ResolverSettings

[evan-bradley]

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Description:

Follows https://github.com/open-telemetry/opentelemetry-collector/pull/9443, relates to https://github.com/open-telemetry/opentelemetry-collector/pull/9513.

This builds on https://github.com/open-telemetry/opentelemetry-collector/pull/9228 to demonstrate the concept.

This shows one way of extending the otelcol APIs to allow passing converters and providers from the builder with the new settings structs for each type.

I think this approach has a few advantages:

1. This follows our pattern of passing in "factory" functions instead of instances to the object that actually uses the instances.
2. Makes the API more declarative: the settings specify which modules to instantiate and which settings to instantiate them with, but don't require the caller to actually do this.
3. Compared to the current state, this allows us to update the config at different layers. A distribution's main.go file can specify the providers/converters it wants and leave the settings to be created by otelcol.Collector.

The primary drawbacks I see here are:

1. This is a little more opinionated since you don't have access to the converter/provider instances or control how they are instantiated. I think this is acceptable and provides good encapsulation.
2. The scheme->provider map can now only be specified by the providers' schemes, which is how it is currently done by default. I would want to hear what use cases we see for more complex control here that necessitates using schemes not specified by the providers.

cc @mx-psi