code: public void deleteUser(String poolId, String nodeId, String userName) {
          deleteUserWithServiceResponseAsync(poolId, nodeId, userName).toBlocking().single().body();
      }
docs: Deletes a user account from the specified compute node.
  You can delete a user account to a node only when it is in the idle or running state.
  
  @param poolId The ID of the pool that contains the compute node.
  @param nodeId The ID of the machine on which you want to delete a user account.
  @param userName The name of the user account to delete.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @throws BatchErrorException thrown if the request is rejected by server
  @throws RuntimeException all other wrapped checked exceptions if the request fails to be sent