Fix `make test:X/Y` where Y is omitted
Fix `make test:X/Y` where Y is omitted

This way, make feature will run all unit tests in feature/* modules.

hlissner/doom-emacs,hlissner/doom-emacs,aminb/.emacs.d,UndeadKernel/emacs_doom,aminb/.emacs.d,hlissner/doom-emacs,hlissner/.emacs.d,UndeadKernel/emacs_doom,hlissner/.emacs.d,aminb/.emacs.d,UndeadKernel/emacs_doom,hlissner/doom-emacs,UndeadKernel/emacs_doom,hlissner/.emacs.d,UndeadKernel/emacs_doom,aminb/.emacs.d,hlissner/.emacs.d,hlissner/.emacs.d,UndeadKernel/emacs_doom,aminb/.emacs.d,UndeadKernel/emacs_doom,hlissner/doom-emacs,hlissner/doom-emacs,aminb/.emacs.d,hlissner/doom-emacs,aminb/.emacs.d,hlissner/.emacs.d,hlissner/.emacs.d,aminb/.emacs.d,hlissner/.emacs.d