Fix warnings in CoordinatorTests (#82764)

Addresses a couple of compiler/IDE warnings in the vicinity of
`CoordinatorTests`.

server/src/test/java/org/elasticsearch/cluster/coordination/CoordinatorTests.java

@@ -172,10 +172,10 @@ public class CoordinatorTests extends AbstractCoordinatorTestCase {
             final ClusterNode leader = cluster.getAnyLeader();
             logger.info("--> adding two new healthy nodes");
             ClusterNode newNode1 = cluster.new ClusterNode(
-                nextNodeIndex.getAndIncrement(), true, leader.nodeSettings, () -> healthStatusInfo.get()
+                nextNodeIndex.getAndIncrement(), true, leader.nodeSettings, healthStatusInfo::get
             );
             ClusterNode newNode2 = cluster.new ClusterNode(
-                nextNodeIndex.getAndIncrement(), true, leader.nodeSettings, () -> healthStatusInfo.get()
+                nextNodeIndex.getAndIncrement(), true, leader.nodeSettings, healthStatusInfo::get
             );
             cluster.clusterNodes.add(newNode1);
             cluster.clusterNodes.add(newNode2);

test/framework/src/main/java/org/elasticsearch/cluster/coordination/AbstractCoordinatorTestCase.java

@@ -51,10 +51,7 @@ import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.transport.TransportAddress;
 import org.elasticsearch.common.unit.ByteSizeValue;
-import org.elasticsearch.common.util.BigArrays;
-import org.elasticsearch.common.util.MockBigArrays;
 import org.elasticsearch.common.util.MockPageCacheRecycler;
-import org.elasticsearch.common.util.PageCacheRecycler;
 import org.elasticsearch.common.util.concurrent.DeterministicTaskQueue;
 import org.elasticsearch.common.util.concurrent.PrioritizedEsThreadPoolExecutor;
 import org.elasticsearch.core.Nullable;
@@ -68,7 +65,6 @@ import org.elasticsearch.gateway.ClusterStateUpdaters;
 import org.elasticsearch.gateway.GatewayService;
 import org.elasticsearch.gateway.MockGatewayMetaState;
 import org.elasticsearch.gateway.PersistedClusterStateService;
-import org.elasticsearch.indices.breaker.NoneCircuitBreakerService;
 import org.elasticsearch.monitor.NodeHealthService;
 import org.elasticsearch.monitor.StatusInfo;
 import org.elasticsearch.test.ESTestCase;
@@ -268,7 +264,6 @@ public class AbstractCoordinatorTestCase extends ESTestCase {
         private final LinearizabilityChecker linearizabilityChecker = new LinearizabilityChecker();
         private final History history = new History();
         private final Recycler<BytesRef> recycler;
-        private final BigArrays bigArrays;
         private final NodeHealthService nodeHealthService;
 
         private final Function<DiscoveryNode, MockPersistedState> defaultPersistedStateSupplier = MockPersistedState::new;
@@ -286,14 +281,9 @@ public class AbstractCoordinatorTestCase extends ESTestCase {
 
         Cluster(int initialNodeCount, boolean allNodesMasterEligible, Settings nodeSettings, NodeHealthService nodeHealthService) {
             this.nodeHealthService = nodeHealthService;
-            if (usually()) {
-                recycler = BytesRefRecycler.NON_RECYCLING_INSTANCE;
-                bigArrays = BigArrays.NON_RECYCLING_INSTANCE;
-            } else {
-                final PageCacheRecycler pageCacheRecycler = new MockPageCacheRecycler(Settings.EMPTY);
-                recycler = new BytesRefRecycler(pageCacheRecycler);
-                bigArrays = new MockBigArrays(pageCacheRecycler, new NoneCircuitBreakerService());
-            }
+            this.recycler = usually()
+                ? BytesRefRecycler.NON_RECYCLING_INSTANCE
+                : new BytesRefRecycler(new MockPageCacheRecycler(Settings.EMPTY));
             deterministicTaskQueue.setExecutionDelayVariabilityMillis(DEFAULT_DELAY_VARIABILITY);
 
             assertThat(initialNodeCount, greaterThan(0));