updated to v2.0.0-a.3, downgraded to java 21

pom.xml

@@ -8,12 +8,12 @@
     <parent>
         <groupId>org.bioimageanalysis.icy</groupId>
         <artifactId>pom-icy</artifactId>
-        <version>3.0.0-a.3</version>
+        <version>3.0.0-a.4</version>
     </parent>
 
     <!-- Project Information -->
     <artifactId>jfreechart</artifactId>
-    <version>2.0.0-a.2</version>
+    <version>2.0.0-a.3</version>
 
     <name>JFreeChart</name>
     <description>