org-return: Do not insert inside folded region

* lisp/org.el (org--newline): When called interactively, check for
invisible edits.

Reported-by: Kaiyu Zheng <kaiyu_zheng@alumni.brown.edu>
Link: https://orgmode.org/list/87wmxs8hxt.fsf@localhost

lisp/org.el

@@ -17663,6 +17663,8 @@ If INDENT is non-nil, call `newline-and-indent' with ARG to
 indent unconditionally; otherwise, call `newline' with ARG and
 INTERACTIVE, which can trigger indentation if
 `electric-indent-mode' is enabled."
+  (when interactive
+    (org-fold-check-before-invisible-edit 'insert))
   (if indent
       (org-newline-and-indent arg)
     (newline arg interactive)))