Enable HTTPS access to LyX repo

[Yuriy Skalko]

Hello all,

Currently LyX repo can be accessed only with SSH (read-write) and Git 
(read-only) protocols.

Git protocol is obsolete and insecure. It is already disabled on GitHub: 
https://github.blog/2021-09-01-improving-git-protocol-security-github/ 
So, I propose to enable HTTPS for read-only access to the repo.

Since https://git.lyx.org/ already runs Apache, I guess these 
instructions can be used for this:
https://wiki.archlinux.org/title/Git_server#Smart_HTTP
https://git-scm.com/book/en/v2/Git-on-the-Server-Smart-HTTP


Best Regards,
Yuriy