Mute SnapshotStressTestsIT.testRandomActivities (#81931)

Due to https://github.com/elastic/elasticsearch/issues/79718

server/src/internalClusterTest/java/org/elasticsearch/snapshots/SnapshotStressTestsIT.java

@@ -79,6 +79,7 @@ import static org.hamcrest.Matchers.notNullValue;
 @LuceneTestCase.SuppressFileSystems(value = "HandleLimitFS") // we sometimes have >2048 open files
 public class SnapshotStressTestsIT extends AbstractSnapshotIntegTestCase {
 
+    @AwaitsFix(bugUrl = "https://github.com/elastic/elasticsearch/issues/79718")
     public void testRandomActivities() throws InterruptedException {
         final DiscoveryNodes discoveryNodes = client().admin().cluster().prepareState().clear().setNodes(true).get().getState().nodes();
         new TrackedCluster(internalCluster(), nodeNames(discoveryNodes.getMasterNodes()), nodeNames(discoveryNodes.getDataNodes())).run();