Bump Java version to 21

Author: kolovos

examples/org.eclipse.epsilon.examples.picto.xtext.domainmodel/domainmodel.target

@@ -8,7 +8,7 @@
 	</location>
 	<location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit">
 		<unit id="org.eclipse.xtext.sdk.feature.group" version="0.0.0"/>
-		unit id="org.eclipse.platform.feature.group" version="0.0.0"/>
+		unit id="org.eclipse.platform.feature.group" version="0.0.0"/&gt;
 		<unit id="org.eclipse.sdk.ide" version="0.0.0"/>
 		<repository location="http://download.eclipse.org/releases/2024-12"/>
 	</location>
@@ -23,8 +23,5 @@
 		<repository location="http://download.eclipse.org/tools/orbit/downloads/drops/R20210223232630/repository"/>
 	</location>
 </locations>
-<targetJRE path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8"/>
-<launcherArgs>
-	<vmArgs>-Dosgi.requiredJavaVersion=1.8</vmArgs>
-</launcherArgs>
-</target>
+<targetJRE path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21"/>
+</target>