refactor(cli): remove :stub, :obsolete, :deprecated, :since

I've removed these CLI properties because they were either
unused (:deprecated and :since) or poorly implemented (:stub and
:obsolete). And I'd rather have fewer magical properties, and instead
delegate these roles to the defobsolete! and (new) defstub!  macros.
Also, in the future, the help API will ascertain :since dynamically, so
it won't be very useful.

In summary:
- Use defstub! instead of :stub
- Use defobsolete! instead of :obsolete or :deprecated
- This removes the doom-cli-deprecated-error type (it's not really an
  error to begin with).
- Removes :stub, :obsolete, :deprecated, and :since

core/cli/make.el

@@ -22,9 +22,8 @@
   :partial t)
 
 ;; TODO Finish and generalize me
-(defcli! (make codeowners) ()
+(defstub! (make codeowners) ()
   "TODO"
-  :stub t
   (print! (start "Generating CODEOWNERS file"))
   (let ((codeowners (doom-path doom-emacs-dir ".github/CODEOWNERS")))
     (with-temp-file codeowners
@@ -41,7 +40,7 @@
                             (match-string-no-properties 2 path)))))))))
 
 ;; TODO Finish me
-(defcli! (make changelog) () :stub t)
+(defstub! (make changelog))