[dd-trace-ot] Ability to customize LogHandler when using the java agent

[ghostdogpr]

I would like to customize the logic of extractError in DefaultLogHandler: https://github.com/DataDog/dd-trace-java/blob/a760c687369c971fa38d95c103883ed672394e6c/dd-trace-ot/src/main/java/datadog/opentracing/DefaultLogHandler.java#L45

For that, I can simply create my own custom LogHandler and then create a new DDTracer:

val ddTracer = DDTracer.builder().logHandler(new CustomLogHandler()).build()

But when I do that it fails with: Datadog Tracer already installed by dd-java-agent. NOTE: Manually creating the tracer while using dd-java-agent is not supported.

Is there a way to pass a custom LogHandler when using the agent?