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/beans-dependencies.xml

@@ -265,7 +265,7 @@ public class ExampleBean {
       </sidebar>
     </section>
 
-    <section>
+    <section id="beans-dependency-resolution">
       <title>Dependency resolution process</title>
 
       <para>The container performs bean dependency resolution as follows:</para>
@@ -859,7 +859,7 @@ support=support@example.co.uk</programlisting>
           the container uses internally.</para>
       </section>
 
-      <section>
+      <section id="beans-collection-merge-limitations">
         <title>Limitations of collection merging</title>
 
         <para>You cannot merge different collection types (such as a