bug#62762: 'make' often errors with "Org version mismatch" after pulling a new version of the code

[Eli Zaretskii]

> From: Ihor Radchenko <yantar92@posteo.net>
> Cc: dmitry@gutov.dev, bzg@gnu.org, 62762@debbugs.gnu.org
> Date: Sat, 15 Apr 2023 11:36:40 +0000
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > I wonder why org--built-in-p is a defconst, though: shouldn't it be a
> > defvar instead?
> 
> I wanted to make it clear that users must not set this variable.
> If you think that it is excessive, I can use defvar instead.

It's up to you, I don't mind.  (But if you decide to go with defconst,
maybe add a comment there explaining that this is the intent.)