Add missing section ids in reference documentation

Add missing id attributes to <section> elements in the reference
documentation to ensure stable anchor links in HTML output.

Issue: SPR-9346

src/reference/docbook/classic-spring.xml

@@ -354,7 +354,7 @@
     <para>...</para>
   </section>
 
-  <section>
+  <section id="classic-spring-jms">
     <title>JMS Usage</title>
 
     <para>One of the benefits of Spring's JMS support is to shield the user
@@ -392,7 +392,7 @@
       </note>
     </sidebar>
 
-    <section>
+    <section id="classic-spring-jms-template">
       <title>JmsTemplate</title>
 
       <para>Located in the package
@@ -407,7 +407,7 @@
       that the point-to-point domain, Queues, will be used.</para>
     </section>
 
-    <section>
+    <section id="classic-spring-aysnc-messages">
       <title>Asynchronous Message Reception </title>
 
       <para><link
@@ -423,7 +423,7 @@
       rely only on the JMS 1.0.2 API. </para>
     </section>
 
-    <section>
+    <section id="classic-spring-jms-connections">
       <title>Connections</title>
 
       <para>The <classname>ConnectionFactory</classname> interface is part of
@@ -441,7 +441,7 @@
       <classname>javax.jmsTopicConnection</classname>.</para>
     </section>
 
-    <section>
+    <section id="classic-spring-jms-tx-management">
       <title>Transaction Management</title>
 
       <para>In a JMS 1.0.2 environment the class