Fix thinko.

src/themes.lisp

@@ -30,7 +30,7 @@ any return value other than nil indicates the injection should be added."
 (defun theme-package (name)
   "Find the package matching the theme NAME or signal THEME-DOES-NOT-EXIST."
   (or (find-package (string-upcase (concatenate 'string "coleslaw.theme." name)))
-      (error 'theme-does-not-exist-error :theme name)))
+      (error 'theme-does-not-exist :theme name)))
 
 (defun theme-fn (name &optional (package (theme *config*)))
   "Find the symbol NAME inside PACKAGE which defaults to the theme package."