What Does This Do

If multiple calls are done to SharedCommunicationObjects.featureDiscovery(..) it might happen that multiple DDAgentFeatureDiscovery instances are created.
This discovery instance must be unique in order to ensure that, tracer-wise, we keep the same vision of the state of the agent.

This PR just add a synchronized block around that creation

Motivation

Additional Notes

Contributor Checklist

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Jira ticket: [PROJ-IDENT]