[FLINK-35468][docs] Simplify `isEnableAutoAcknowledgeMessage` config comment

diff --git a/flink-connector-pulsar/src/main/java/org/apache/flink/connector/pulsar/source/config/SourceConfiguration.java b/flink-connector-pulsar/src/main/java/org/apache/flink/connector/pulsar/source/config/SourceConfiguration.java
index 765db30..f6999c4 100644
--- a/flink-connector-pulsar/src/main/java/org/apache/flink/connector/pulsar/source/config/SourceConfiguration.java
+++ b/flink-connector-pulsar/src/main/java/org/apache/flink/connector/pulsar/source/config/SourceConfiguration.java
@@ -112,15 +112,12 @@
     }
 
     /**
-     * This is used for all subscription type. But the behavior may not be the same among them. If
-     * you don't enable the flink checkpoint, make sure this option is set to true.
+     * This is used for all subscription type.
+     * If you don't enable the flink checkpoint, please make sure this option is set to true.
+     * <p>
+     * {@link SubscriptionType#Failover} and {@link SubscriptionType#Exclusive} would perform
+     *  an incremental acknowledgment in a fixed {@link #getAutoCommitCursorInterval}.
      *
-     * <ul>
-     *   <li>{@link SubscriptionType#Shared} and {@link SubscriptionType#Key_Shared} would
-     *       immediately acknowledge the message after consuming it.
-     *   <li>{@link SubscriptionType#Failover} and {@link SubscriptionType#Exclusive} would perform
-     *       a incremental acknowledge in a fixed {@link #getAutoCommitCursorInterval}.
-     * </ul>
      */
     public boolean isEnableAutoAcknowledgeMessage() {
         return enableAutoAcknowledgeMessage;