ci: update emacs stable versions

Author: Silex

.github/workflows/test.yml

@@ -14,7 +14,7 @@ jobs:
     strategy:
       matrix:
         # Earliest supported + latest in each stable branch + snapshot.
-        emacs_version: ['26.3', '27.1', '28.1', '29.1', 'snapshot']
+        emacs_version: ['26.3', '27.2', '28.2', '29.4', 'snapshot']
 
     steps:
     - name: Set up Emacs