@VisibleForTesting
  Optional<DiagnosticsManager> buildDiagnosticsManager(String jobName, String jobId, JobModel jobModel,
      String containerId, Optional<String> executionEnvContainerId, Optional<String> samzaEpochId,
      Config config) {
    return DiagnosticsUtil.buildDiagnosticsManager(jobName, jobId, jobModel, containerId, executionEnvContainerId,
        samzaEpochId, config);
  }
Wrapper around {@link DiagnosticsUtil#buildDiagnosticsManager} so it can be stubbed during testing.
samza-core/src/main/java/org/apache/samza/coordinator/staticresource/StaticResourceJobCoordinator.java