Add Emacs 28.2 to CI, cut down size of matrix

Author: purcell

.github/workflows/test.yml

@@ -12,19 +12,15 @@ jobs:
       matrix:
         emacs_version:
           - 24.1
-          - 24.2
-          - 24.3
-          - 24.4
           - 24.5
           - 25.1
-          - 25.2
           - 25.3
           - 26.1
-          - 26.2
           - 26.3
           - 27.1
           - 27.2
           - 28.1
+          - 28.2
           - snapshot
     steps:
     - uses: purcell/setup-emacs@master