private void waitUntil(BooleanSupplier booleanSupplier, String messageIfWaitingFails) throws InterruptedException {
        Duration timeout = Duration.ofSeconds(60);
        Instant endTime = Instant.now().plus(timeout);
        while (Instant.now().isBefore(endTime)) {
            if (booleanSupplier.getAsBoolean())
                return;
            Thread.sleep(10);
        }
        throw new RuntimeException(messageIfWaitingFails);
    }
@author Ulf Lilleengen
@author Harald Musum
configserver/src/test/java/com/yahoo/vespa/config/server/ConfigServerBootstrapTest.java