Bump minimum emacs version

Otherwise CI fails, seems like Cask doesn't support older versions?

Author: davidshepherd7

.github/workflows/main.yml

@@ -23,7 +23,6 @@ jobs:
     strategy:
       matrix:
         emacs_version:
-          - 25.3
           - 26.3
           - 27.1
       fail-fast: false

frames-only-mode.el

@@ -4,7 +4,7 @@
 
 ;; Author: David Shepherd <davidshepherd7@gmail.com>
 ;; Version: 1.0.0
-;; Package-Requires: ((emacs "24.4") (dash "2.13.0") (s "1.11.0"))
+;; Package-Requires: ((emacs "26.3") (dash "2.13.0") (s "1.11.0"))
 ;; Keywords: frames, windows
 ;; URL: https://github.com/davidshepherd7/frames-only-mode