public void restartWorkflow(String workflowId, boolean useLatestDefinitions) {
        workflowExecutor.restart(workflowId, useLatestDefinitions);
    }
Restarts a completed workflow.

@param workflowId WorkflowId of the workflow.
@param useLatestDefinitions if true, use the latest workflow and task definitions upon
    restart
core/src/main/java/com/netflix/conductor/service/WorkflowServiceImpl.java