feat: Drop 27.x due to upstream markdown-mode

Author: jcs090218

Eask

@@ -16,7 +16,7 @@
 (source 'gnu)
 (source 'melpa)
 
-(depends-on "emacs" "27.1")
+(depends-on "emacs" "28.1")
 (depends-on "openai")
 (depends-on "lv")
 (depends-on "ht")

chatgpt.el

@@ -6,7 +6,7 @@
 ;; Maintainer: Shen, Jen-Chieh <[email protected]>
 ;; URL: https://github.com/emacs-openai/chatgpt
 ;; Version: 0.1.0
-;; Package-Requires: ((emacs "27.1") (openai "0.1.0") (lv "0.0") (ht "2.0") (markdown-mode "2.1") (spinner "1.7.4"))
+;; Package-Requires: ((emacs "28.1") (openai "0.1.0") (lv "0.0") (ht "2.0") (markdown-mode "2.1") (spinner "1.7.4"))
 ;; Keywords: comm openai
 
 ;; This file is not part of GNU Emacs.