Mute disruption tests for jdk20+ (#94207) (#94254)

In JDK 20 Thread suspend/resume is soft removed (they now throw
UnsupportedOperationException). Many ES disruption tests simulate GC
pauses with suspend/resume. As that strategy will no longer work, this
commit mutes those tests for jdk20+.

relates #94206
closes #93707

server/src/internalClusterTest/java/org/elasticsearch/discovery/StableMasterDisruptionIT.java

@@ -22,6 +22,7 @@
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.util.set.Sets;
 import org.elasticsearch.core.Tuple;
+import org.elasticsearch.jdk.JavaVersion;
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.test.ESIntegTestCase;
 import org.elasticsearch.test.disruption.LongGCDisruption;
@@ -172,6 +173,7 @@ private void testFollowerCheckerAfterMasterReelection(NetworkLinkDisruptionType
      * following another elected master node. These nodes should reject this cluster state and prevent them from following the stale master.
      */
     public void testStaleMasterNotHijackingMajority() throws Exception {
+        assumeFalse("jdk20 removed thread suspend/resume", JavaVersion.current().compareTo(JavaVersion.parse("20")) >= 0);
         final List<String> nodes = internalCluster().startNodes(
             3,
             Settings.builder()

test/framework/src/test/java/org/elasticsearch/test/disruption/LongGCDisruptionTests.java

@@ -8,7 +8,9 @@
 package org.elasticsearch.test.disruption;
 
 import org.elasticsearch.core.Nullable;
+import org.elasticsearch.jdk.JavaVersion;
 import org.elasticsearch.test.ESTestCase;
+import org.junit.BeforeClass;
 
 import java.lang.management.ThreadInfo;
 import java.util.ArrayList;
@@ -40,6 +42,11 @@ public void executeLocked(Runnable r) {
         }
     }
 
+    @BeforeClass
+    public static void ignoreJdk20Plus() {
+        assumeFalse("jdk20 removed thread suspend/resume", JavaVersion.current().compareTo(JavaVersion.parse("20")) >= 0);
+    }
+
     public void testBlockingTimeout() throws Exception {
         final String nodeName = "test_node";
         LongGCDisruption disruption = new LongGCDisruption(random(), nodeName) {