bug#61976: [elpa/yasnippet] [PATCH] Fix compilation warnings in Emacs 29

[Stefan Monnier]

> This one enabling lexical-binding might be a bit more work, or no work.
> No idea which.  It would be nice to have, in any case:
>
>     https://github.com/joaotavora/yasnippet/pull/1053

The code up on `scratch/yasnippet` (inside `elpa.git`) also activates
lexical-binding (tho I can't remember if it actively makes use of it in
a way that makes it incompatible with Emacs-23).


        Stefan