fix: disabled Choice binding shortcut_key (#334)

questionary/prompts/select.py

@@ -200,7 +200,7 @@ def _(event):
                     "for movement are disabled. "
                     "This choice is not reachable.".format(c.title)
                 )
-            if isinstance(c, Separator) or c.shortcut_key is None:
+            if isinstance(c, Separator) or c.shortcut_key is None or c.disabled:
                 continue
 
             # noinspection PyShadowingNames