Adapt to changed output directory in maven-javadoc-plugin 3.10.0

Fixes #1392

Author: HannesWell

org.eclipse.pde.doc.user/forceQualifierUpdate.txt

@@ -2,4 +2,5 @@
 Fix deprecation tag 'since' value
 Modernize pde.project description interfaces: https://github.com/eclipse-pde/eclipse.pde/pull/1341
 Rework PluginRegistry API and introduce VersionMatchRule enum : https://github.com/eclipse-pde/eclipse.pde/pull/1163
-Comparator errors in I20240904-0240
+Comparator errors in I20240904-0240
+Add missing reference/api content

org.eclipse.pde.doc.user/pom.xml

@@ -228,7 +228,7 @@
                   <outputDirectory>${basedir}/reference/api</outputDirectory>
                   <resources>          
                     <resource>
-                      <directory>${project.build.directory}/site/apidocs</directory>
+                      <directory>${project.build.directory}/reports/apidocs</directory>
                     </resource>
                   </resources>
                 </configuration>