refactor(rmi): remove ClientUtil and simplify stub creation

Remove the ClientUtil utility class that was used to check if running
as a client container. This check is no longer needed, so the stub
creation logic in PortableRemoteObjectImpl has been simplified to
directly call state.createRMIStub(type).

Changes:
- Removed ClientUtil.java
- Removed ClientUtil import from PortableRemoteObjectImpl
- Simplified createStub() method to remove Optional filter chain

Co-authored-by-AI: IBM Bob 2.0.0

Author: joe-chacko

yoko-rmi-impl/src/main/java/org/apache/yoko/rmi/impl/PortableRemoteObjectImpl.java

@@ -17,7 +17,6 @@
  */
 package org.apache.yoko.rmi.impl;
 
-import org.apache.yoko.rmi.util.ClientUtil;
 import org.omg.CORBA.BAD_INV_ORDER;
 import org.omg.CORBA.BAD_OPERATION;
 import org.omg.CORBA.portable.Delegate;
@@ -180,10 +179,7 @@ private static Stub createStub(Class<?> type) {
         if (Remote.class == type) return new RMIRemoteStub();
 
         RMIState state = RMIState.current();
-        return Optional.of(state)
-                .filter(s -> ClientUtil.isRunningAsClientContainer())
-                .map(s -> s.getStaticStub(null, type))
-                .orElseGet(() -> state.createRMIStub(type));
+        return state.createRMIStub(type);
     }
 
     public Remote toStub(Remote value) throws NoSuchObjectException {