[misc] Make sure archetypes are generated with the right versions

pom.xml

@@ -53,7 +53,8 @@
     <xwiki.compatibility.previous.version>13.10.1</xwiki.compatibility.previous.version>
 
     <!-- Java -->
-    <java.version>1.8</java.version>
+    <xwiki.java.version>1.8</xwiki.java.version>
+    <java.version>${xwiki.java.version}</java.version>
 
     <!-- Jakarta modules -->
     <jakarta.mail.version>1.6.7</jakarta.mail.version>
@@ -212,6 +213,9 @@
     <!-- The version of the Maven Remote Resource plugin -->
     <maven-remote-resources-plugin.version>1.7.0</maven-remote-resources-plugin.version>
 
+    <!-- The version of the Maven Compiler Plugin -->
+    <maven.compiler.version>3.9.0</maven.compiler.version>
+
     <!-- The version of Eclipse Sisu to use-->
     <sisu.version>0.3.5</sisu.version>
 
@@ -2036,7 +2040,7 @@
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-compiler-plugin</artifactId>
           <!-- Lock down plugin version for build reproducibility -->
-          <version>3.9.0</version>
+          <version>${maven.compiler.version}</version>
           <configuration>
             <source>${java.version}</source>
             <target>${java.version}</target>

xwiki-commons-core/xwiki-commons-component/xwiki-commons-component-archetype/src/main/resources/archetype-resources/pom.xml

@@ -36,10 +36,10 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-compiler-plugin</artifactId>
-        <version>3.8.1</version>
+        <version>${maven.compiler.version}</version>
         <configuration>
-          <source>1.8</source>
-          <target>1.8</target>
+          <source>${xwiki.java.version}</source>
+          <target>${xwiki.java.version}</target>
         </configuration>
       </plugin>
       <plugin>