bug#61223: 29.0.60; treesit--install-language-grammar-build-recipe refers github

[Yuan Fu]

X-Debbugs-CC: eliz@gnu.org, dgutov@yandex.ru
--text follows this line--
I noticed that treesit-install-language-grammar now automatically builds
the repository url from github:

(let ((repo-default (format "https://github.com/tree-sitter/tree-sitter-%s"; 
lang)))
         (read-string
          "Enter the URL of the Git repository of the language grammar: "
          (and (treesit--check-repo-url repo-default) repo-default)))


AFAICT GNU don’t want to promote/refer to github, that’s why I didn’t
include “official” grammar repositories in
treesit-language-source-alist. Was there a discussion that I missed?

This is a nice feature, but I’d hate having to remove it later, after
users have noticed it and started using/depending on it, due to some GNU
policy.

Yuan