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/main/java/org/elasticsearch/cluster/coordination/ClusterBootstrapService.java
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.common.ReferenceDocs;
import org.elasticsearch.common.settings.Setting;
import org.elasticsearch.common.settings.Setting.Property;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.core.Nullable;
import org.elasticsearch.core.TimeValue;
import org.elasticsearch.core.Tuple;
import org.elasticsearch.discovery.DiscoveryModule;
import org.elasticsearch.node.Node;
import org.elasticsearch.threadpool.ThreadPool.Names;
import org.elasticsearch.transport.TransportService;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.function.BooleanSupplier;
import java.util.function.Consumer;
import java.util.function.Supplier;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;
import static java.util.Collections.emptyList;
import static java.util.Collections.unmodifiableSet;
import static org.elasticsearch.discovery.DiscoveryModule.DISCOVERY_SEED_PROVIDERS_SETTING;
import static org.elasticsearch.discovery.SettingsBasedSeedHostsProvider.DISCOVERY_SEED_HOSTS_SETTING;
public class ClusterBootstrapService implements Coordinator.PeerFinderListener {