* guix/build-system/emacs.scm (emacs-build): Add #:test-command keyword argument. Remove #:configure-flags and #:test-target keyword arguments. * guix/build/emacs-build-system.scm (check): New procedure. (%standard-phases): Register check phase after the build phase. Signed-off-by: Arun Isaac <arunisaac@systemreboot.net>