Rename unmap! to undefine-key!

unmap! gives the false impression that it is related or similar to map!,
but it isn't.

core/core-keybinds.el

@@ -77,7 +77,8 @@ all hooks after it are ignored.")
   :init
   ;; Convenience aliases
   (defalias 'define-key! #'general-def)
-  (defalias 'unmap! #'general-unbind))
+  (defalias 'undefine-key! #'general-unbind))
+
 
 ;; HACK `map!' uses this instead of `define-leader-key!' because it consumes
 ;; 20-30% more startup time, so we reimplement it ourselves.

docs/getting_started.org

@@ -910,7 +910,7 @@ also be helpful for debugging.
 + define-key
 + global-set-key
 + map!
-+ unmap!
++ undefine-key!
 + define-key!
 
 ** Writing your own modules

modules/tools/magit/config.el

@@ -162,7 +162,7 @@ ensure it is built when we actually use Forge."
   (setq evil-magit-state 'normal
         evil-magit-use-z-for-folds t)
   :config
-  (unmap! magit-mode-map
+  (undefine-key! magit-mode-map
     ;; Replaced by z1, z2, z3, etc
     "M-1" "M-2" "M-3" "M-4"
     "1" "2" "3" "4"