fix: visit non-attached java-docs (comments) same as the rest of the …

…java-docs

gen.jdt/src/main/java/com/github/gumtreediff/gen/jdt/JdtWithCommentsVisitor.java

@@ -52,12 +52,12 @@ public boolean visit(LineComment node) {
         }
 
         public boolean visit(Javadoc node) {
-            //We have to check if the java doc is attached to any program element or not
+            //We have to check if the Javadoc is attached to any program element or not
             //The attached ones, have been already visited, and we do not want to add them twice.
             if (node.getParent() == null)
-                //Then it is javadoc which is attached to any program element,
-                //So it will be visited as same as the other comments but with JavaDoc label
-                return visitComment(node);
+                //Then it is Javadoc attached to any program element,
+                //So we do as the same as the other Javadocs in the original visitors
+                node.accept(JdtWithCommentsVisitor.this);
             return true;
         }