feat: Drop Emacs 26.x support

Author: jcs090218

Eask

@@ -14,7 +14,7 @@
 (source 'melpa)
 (source 'gnu)
 
-(depends-on "emacs" "26.1")
+(depends-on "emacs" "27.1")
 (depends-on "php-runtime")
 (depends-on "composer")
 (depends-on "async")

phpactor.el

@@ -7,7 +7,7 @@
 ;; Created: 8 Apr 2018
 ;; Version: 0.1.0
 ;; Keywords: tools, php
-;; Package-Requires: ((emacs "26.1") (php-runtime "0.2") (composer "0.2.0") (async "1.9.3"))
+;; Package-Requires: ((emacs "27.1") (php-runtime "0.2") (composer "0.2.0") (async "1.9.3"))
 ;; URL: https://github.com/emacs-php/phpactor.el
 ;; License: GPL-3.0-or-later