Fix documentation comment in generated with templates files

Fix warning
```
/******************************************************************************/
^
warning: [dangling-doc-comments] documentation comment is not attached to any declaration

```
in Nodes.java and AbstractNodeVisitor.java files. /** is treated as a starting of a javadoc comment.

Author: andrykonchin

templates/template.rb

@@ -559,13 +559,13 @@ def render(name, write_to: nil)
             HEADING
           else
             <<~HEADING
-            /******************************************************************************/
+            /*----------------------------------------------------------------------------*/
             /* This file is generated by the templates/template.rb script and should not  */
             /* be modified manually. See                                                  */
             /* #{filepath + " " * (74 - filepath.size) } */
             /* if you are looking to modify the                                           */
             /* template                                                                   */
-            /******************************************************************************/
+            /*----------------------------------------------------------------------------*/
 
             HEADING
           end