static void forceRenounce(QuorumController controller) throws Exception {
        CompletableFuture<Void> future = new CompletableFuture<>();
        controller.appendControlEvent("forceRenounce", () -> {
            controller.renounce();
            future.complete(null);
        });
        future.get(30, TimeUnit.SECONDS);
    }
Force the current controller to renounce.

@param controller    The controller.
metadata/src/test/java/org/apache/kafka/controller/QuorumControllerIntegrationTestUtils.java