private void waitForClientToFullyConnect(PoolImpl pool) {
    long failMillis = System.currentTimeMillis() + JOIN_FAIL_MILLIS;
    boolean fullyConnected = false;
    while (!fullyConnected) {
      pause(100);
      fullyConnected = pool.getConnectionCount() >= pool.getMinConnections();
      assertThat(System.currentTimeMillis()).isLessThan(failMillis);
    }
  }
Waits for client to create an expected number of connections. Note: This probably won't work if
the pool has more than one Endpoint.
geode-core/src/distributedTest/java/org/apache/geode/management/UniversalMembershipListenerAdapterDUnitTest.java