Make resourcedetectionprocessor available in otel mode

[ycombinator]

Describe the enhancement:

Include the resourcedetectionprocessor in the OTel Collector components we bundle with Elastic Agent.

Describe a specific use case for the enhancement or feature:

Users of Elastic Agent in OTel mode (elastic-agent otel ...) would like to be able to use the resourcedetectionprocessor in their OTel Collector pipeline configurations.

What is the definition of done?

• A test that runs Elastic Agent in OTel mode (elastic-agent otel ...) includes the resourcedetectionprocessor in it's test OTel Collector configuration and the test passes.

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)