When users login gitea on a headless server via ssh, xdg-open might not be installed on that machine. So tea may fail to open URL itself. In this case, users can use the other machine to open the URL for authentication.
Github CLI act like this, too.
Signed-off-by: Chen Linxuan <me@black-desk.cn>
Reviewed-on: https://gitea.com/gitea/tea/pulls/794
Reviewed-by: blumia <blumia@noreply.gitea.com>
Co-authored-by: Chen Linxuan <me@black-desk.cn>
Co-committed-by: Chen Linxuan <me@black-desk.cn>
