Fix BanFailureLoggingTests (#75171)

Today both `BanFailureLoggingTests` fail to remove the ban and report
this in the logs. `testLogsAtDebugOnDisconnectionDuringBan` does not
wait for this message to be logged, so the logging might happen
concurrently with the logger being stopped and removed, resulting in a
`Attempted to append to non-started appender mock` failure.

This commit ensures that both test cases wait for the expected removal
failure message to be logged.

Closes #75129

Author: DaveCTurner

server/src/test/java/org/elasticsearch/tasks/BanFailureLoggingTests.java

@@ -33,7 +33,9 @@
 
 import java.io.Closeable;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
+import java.util.List;
 import java.util.Map;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.function.Function;
@@ -52,11 +54,17 @@ public void testLogsAtDebugOnDisconnectionDuringBan() throws Exception {
                 }
                 connection.sendRequest(requestId, action, request, options);
             },
-            childNode -> new MockLogAppender.SeenEventExpectation(
-                "cannot send message",
-                TaskCancellationService.class.getName(),
-                Level.DEBUG,
-                "*cannot send ban for tasks*" + childNode.getId() + "*"));
+            childNode -> Arrays.asList(
+                new MockLogAppender.SeenEventExpectation(
+                    "cannot send ban",
+                    TaskCancellationService.class.getName(),
+                    Level.DEBUG,
+                    "*cannot send ban for tasks*" + childNode.getId() + "*"),
+                new MockLogAppender.SeenEventExpectation(
+                    "cannot remove ban",
+                    TaskCancellationService.class.getName(),
+                    Level.DEBUG,
+                    "*failed to remove ban for tasks*" + childNode.getId() + "*")));
     }
 
     @TestLogging(reason = "testing logging at DEBUG", value = "org.elasticsearch.tasks.TaskCancellationService:DEBUG")
@@ -69,16 +77,22 @@ public void testLogsAtDebugOnDisconnectionDuringBanRemoval() throws Exception {
                 }
                 connection.sendRequest(requestId, action, request, options);
             },
-            childNode -> new MockLogAppender.SeenEventExpectation(
-                "cannot send message",
-                TaskCancellationService.class.getName(),
-                Level.DEBUG,
-                "*failed to remove ban for tasks*" + childNode.getId() + "*"));
+            childNode -> Arrays.asList(
+                new MockLogAppender.UnseenEventExpectation(
+                    "cannot send ban",
+                    TaskCancellationService.class.getName(),
+                    Level.DEBUG,
+                    "*cannot send ban for tasks*" + childNode.getId() + "*"),
+                new MockLogAppender.SeenEventExpectation(
+                    "cannot remove ban",
+                    TaskCancellationService.class.getName(),
+                    Level.DEBUG,
+                    "*failed to remove ban for tasks*" + childNode.getId() + "*")));
     }
 
     private void runTest(
         StubbableTransport.SendRequestBehavior sendRequestBehavior,
-        Function<DiscoveryNode, MockLogAppender.SeenEventExpectation> expectation) throws Exception {
+        Function<DiscoveryNode, List<MockLogAppender.LoggingExpectation>> expectations) throws Exception {
 
         final ArrayList<Closeable> resources = new ArrayList<>(3);
 
@@ -140,7 +154,9 @@ public Task createTask(long id, String type, String action, TaskId parentTaskId,
             Loggers.addAppender(LogManager.getLogger(TaskCancellationService.class), appender);
             resources.add(() -> Loggers.removeAppender(LogManager.getLogger(TaskCancellationService.class), appender));
 
-            appender.addExpectation(expectation.apply(childTransportService.getLocalDiscoNode()));
+            for (MockLogAppender.LoggingExpectation expectation : expectations.apply(childTransportService.getLocalDiscoNode())) {
+                appender.addExpectation(expectation);
+            }
 
             final PlainActionFuture<Void> cancellationFuture = new PlainActionFuture<>();
             parentTransportService.getTaskManager().cancelTaskAndDescendants(parentTask, "test", true, cancellationFuture);