Remove duplicate condition check in ZooKeeperLeaderElectionService

@Override
public boolean hasLeadership() {
  if(leaderLatch.getState().equals(LeaderLatch.State.STARTED)) {
    return leaderLatch.hasLeadership();
  } else {
    return false;
  }
}

return (state.get() == State.STARTED) && hasLeadership.get();