In #86101 we added a warning if bootstrapping was incorrectly configured (and in #92744 we changed it to be emitted every 12h). The logic introduced doesn't take account of `discovery.type: single-node`, so explicitly-single-node clusters will always emit this warning even though they are correctly configured.

Relates https://github.com/elastic/elasticsearch/issues/58393.
server/src/test/java/org/elasticsearch/cluster/coordination/ClusterBootstrapServiceTests.java
private DiscoveryNode localNode, otherNode1, otherNode2;
    private DeterministicTaskQueue deterministicTaskQueue;
    private TransportService transportService;
    @Before
    public void createServices() {
        localNode = newDiscoveryNode("local");
        otherNode1 = newDiscoveryNode("other1");
        otherNode2 = newDiscoveryNode("other2");
        deterministicTaskQueue = new DeterministicTaskQueue();
        final MockTransport transport = new MockTransport() {
            @Override
            protected void onSendRequest(long requestId, String action, TransportRequest request, DiscoveryNode node) {
                throw new AssertionError("unexpected " + action);
            }
        };
        transportService = transport.createTransportService(
            Settings.EMPTY,
            deterministicTaskQueue.getThreadPool(),
            TransportService.NOOP_TRANSPORT_INTERCEPTOR,
            boundTransportAddress -> localNode,
            null,
            emptySet()
        );
    }
    private DiscoveryNode newDiscoveryNode(String nodeName) {
        return DiscoveryNodeUtils.builder(randomAlphaOfLength(10)).name(nodeName).roles(Set.of(DiscoveryNodeRole.MASTER_ROLE)).build();
    }
    public void testBootstrapsAutomaticallyWithDefaultConfiguration() {
        final Settings.Builder settings = Settings.builder();