Consider removing newlines from org-insert-link help message

[Salih Muhammed]

https://git.savannah.gnu.org/cgit/emacs/org-mode.git/tree/lisp/ol.el#n1856

        (insert "Insert a link.
Use TAB to complete link prefixes, then RET for type-specific completion 
support\n")

This causes a stretch in the message buffer, which sometimes is being a
little bit annoying, I'm advising org-link-insert personally because of
it.

Maybe merging it into one line:

        (insert "Insert a link. Use TAB to complete link prefixes, then RET for 
type-specific completion support\n")

Will make it better.

--
Regards,
Salih