Use java21 profile for jena 6

Author: acoburn

pom.xml

@@ -28,7 +28,7 @@
     <guava.version>33.5.0-jre</guava.version>
     <jackson.version>2.21.1</jackson.version>
     <jakarta.json.version>2.1.3</jakarta.json.version>
-    <jena.version>6.0.0</jena.version>
+    <jena.version>5.6.0</jena.version>
     <jose4j.version>0.9.6</jose4j.version>
     <json.bind.version>3.0.1</json.bind.version>
     <okhttp.version>5.3.2</okhttp.version>
@@ -768,6 +768,15 @@
   </reporting>
 
   <profiles>
+    <profile>
+      <id>jena6</id>
+      <activation>
+        <jdk>[21,)</jdk>
+      </activation>
+      <properties>
+        <jena.version>6.0.0</jena.version>
+      </properties>
+    </profile>
     <profile>
       <id>publish</id>
       <!-- skip tests for publish profile, since these tests have already run -->