* Makefile.am (GUIX_GIT_KEYRING): New variable. (authenticate): Use GUIX_GIT_KEYRING to select the keyring branch reference. * doc/contributing.texi (Building from Git): Add an example about the use of GUIX_GIT_KEYRING.
* Makefile.am (GUIX_GIT_KEYRING): New variable. (authenticate): Use GUIX_GIT_KEYRING to select the keyring branch reference. * doc/contributing.texi (Building from Git): Add an example about the use of GUIX_GIT_KEYRING.