Directly set variable to always create ID properties for links

This is mostly because I haven't had time to understand what the `:custom`
keyword is actually doing.  Apparently, it introduces customizations without
user interaction, which in turn makes changing default values a manual
process (by changing customizations one has never done) thus resulting in
inconsistent behavior.

init.el

@@ -929,7 +929,7 @@
   :commands (org-store-link))
 
 (use-package org-id
-  :custom (org-id-link-to-org-use-id t))
+  :init (setq org-id-link-to-org-use-id t))
 
 (use-package org-clock
   :commands (org-clock-save)