Update call-c-from-java.yaml

IO.println is Java 25, but slug's "new" is 22+.

Author: IanDarwin

content/language/call-c-from-java.yaml

@@ -38,7 +38,7 @@ modernCode: |-
           var strlenSig = FunctionDescriptor.of(ValueLayout.JAVA_LONG, ValueLayout.ADDRESS);
           var strlenMethod = Linker.nativeLinker() .downcallHandle(foreignFuncAddr, strlenSig);
           var ret = (long) strlenMethod.invokeExact(arena.allocateFrom("Bambi"));
-          IO.println("Return value " + ret); // 5
+          System.out.println("Return value " + ret); // 5
       }
   }