Fix issue where Key_Shared consumers could get stuck (apache#10920)

pulsar-broker/src/main/java/org/apache/pulsar/broker/service/persistent/PersistentStickyKeyDispatcherMultipleConsumers.java

@@ -121,8 +121,14 @@ public synchronized void addConsumer(Consumer consumer) throws BrokerServiceExce
 
     @Override
     public synchronized void removeConsumer(Consumer consumer) throws BrokerServiceException {
-        super.removeConsumer(consumer);
+        // The consumer must be removed from the selector before calling the superclass removeConsumer method.
+        // In the superclass removeConsumer method, the pending acks that the consumer has are added to
+        // messagesToRedeliver. If the consumer has not been removed from the selector at this point,
+        // the broker will try to redeliver the messages to the consumer that has already been closed.
+        // As a result, the messages are not redelivered to any consumer, and the mark-delete position does not move,
+        // eventually causing all consumers to get stuck.
         selector.removeConsumer(consumer);
+        super.removeConsumer(consumer);
         if (recentlyJoinedConsumers != null) {
             recentlyJoinedConsumers.remove(consumer);
             if (consumerList.size() == 1) {