[hotfix][table][docs] correct distinct operator doc for table API.

this closes apache#8470

docs/dev/table/tableApi.md

@@ -631,7 +631,7 @@ orders.groupBy("users").select("users, myUdagg.distinct(points) as myDistinctRes
 Table orders = tableEnv.scan("Orders");
 Table result = orders.distinct();
 {% endhighlight %}
-        <p><b>Note:</b> For streaming queries the required state to compute the query result might grow infinitely depending on the number of distinct fields. Please provide a query configuration with valid retention interval to prevent excessive state size. See <a href="streaming/query_configuration.html">Query Configuration</a> for details.</p>
+        <p><b>Note:</b> For streaming queries the required state to compute the query result might grow infinitely depending on the number of distinct fields. Please provide a query configuration with valid retention interval to prevent excessive state size. If state cleaning is enabled, distinct have to emit messages to prevent too early state eviction of downstream operators which makes distinct contains result updating. See <a href="streaming/query_configuration.html">Query Configuration</a> for details.</p>
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@@ -743,15 +743,16 @@ orders.groupBy('users).select('users, myUdagg.distinct('points) as 'myDistinctRe
     <tr>
       <td>
         <strong>Distinct</strong><br>
-        <span class="label label-primary">Batch</span>
+        <span class="label label-primary">Batch</span> <span class="label label-primary">Streaming</span> <br>
+        <span class="label label-info">Result Updating</span>
       </td>
       <td>
         <p>Similar to a SQL DISTINCT clause. Returns records with distinct value combinations.</p>
 {% highlight scala %}
 val orders: Table = tableEnv.scan("Orders")
 val result = orders.distinct()
 {% endhighlight %}
-        <p><b>Note:</b> For streaming queries the required state to compute the query result might grow infinitely depending on the number of distinct fields. Please provide a query configuration with valid retention interval to prevent excessive state size. See <a href="streaming/query_configuration.html">Query Configuration</a> for details.</p>
+        <p><b>Note:</b> For streaming queries the required state to compute the query result might grow infinitely depending on the number of distinct fields. Please provide a query configuration with valid retention interval to prevent excessive state size. If state cleaning is enabled, distinct have to emit messages to prevent too early state eviction of downstream operators which makes distinct contains result updating. See <a href="streaming/query_configuration.html">Query Configuration</a> for details.</p>
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