Nitpick: Make org-super-links-convert-link-to-super argument optional

[meedstrom]

I propose changing the arglist for function org-super-links-convert-link-to-super into (&optional arg). That way, I can hook it on org-node link insertion

(add-hook 'org-node-insert-link-hook #'org-super-links-convert-link-to-super)

without writing a wrapper. That'll look nice.

Right now I have this wrapper

(defun org-node-convert-link-to-super ()
  "Call `org-super-links-convert-link-to-super' with nil argument."
  (require 'org-super-links)
  (when (fboundp 'org-super-links-convert-link-to-super)
    (org-super-links-convert-link-to-super nil)))