protected static void stopLocator() {
    MembershipManagerHelper.inhibitForcedDisconnectLogging(false);
    Locator loc = Locator.getLocator();
    if (loc != null) {
      loc.stop();
      assertThat(Locator.hasLocator()).isFalse();
    }
  }
find the lead member and return its id
geode-core/src/distributedTest/java/org/apache/geode/distributed/LocatorDUnitTest.java