[FIX] incorrect newapi migration in website_blog

Leads to the Duplicate link (when editing a blog post in website)
yielding a 500 Internal Error instead of duplicating the blog post.

OPW-740308

Fixes #16511

addons/website_blog/controllers/main.py

@@ -322,7 +322,7 @@ class WebsiteBlog(http.Controller):
 
         :return redirect to the new blog created
         """
-        new_blog_post = request.env['blog.post'].with_context(mail_create_nosubscribe=True).copy(int(blog_post_id), {})
+        new_blog_post = request.env['blog.post'].with_context(mail_create_nosubscribe=True).browse(int(blog_post_id)).copy()
         return werkzeug.utils.redirect("/blog/%s/post/%s?enable_editor=1" % (slug(new_blog_post.blog_id), slug(new_blog_post)))
 
     @http.route('/blog/post_get_discussion/', type='json', auth="public", website=True)