bug#41198: 28.0.50; heading cycling command for outline

[Juri Linkov]

>> 2x patches attached with changelog.
>
> Thanks; looks OK to me, so I've applied it to Emacs 28.

BTW, since now S-TAB cycles headings nicely in etc/NEWS,
what about enabling outline-minor-mode in the output
Help buffer of 'C-h b'?  Currently its section
"Key translations" is so long that it takes too much time
to scroll down to the most interesting section
"Major Mode Bindings".  With outline-minor-mode it would
be possible to collapse "Key translations" initially.
Then typing S-TAB would show such nice overview:

* Key translations
* `override-global-mode' Minor Mode Bindings
* `outline-minor-mode' Minor Mode Bindings
* recentf-mode Minor Mode Bindings
* Major Mode Bindings
* Global Bindings
* Function key map translations
* Input decoding map translations