ox-latex: Fix defcustom keywords.

* lisp/ox-latex.el (org-latex-reference-command): Do not provide
both :version and :package-version.  Add :safe keyword.

lisp/ox-latex.el

@@ -412,8 +412,8 @@ use of a package such as hyperref or cleveref and then change the format string
 to \"\\autoref{%s}\" or \"\\cref{%s}\" for example."
   :group 'org-export-latex
   :type 'string
-  :version "28.1"
-  :package-version '(Org . "9.5"))
+  :package-version '(Org . "9.5")
+  :safe t)
 
 ;;;; Preamble