ci: Bump Emacs 29.x to 3

Author: jcs090218

.github/workflows/test.yml

@@ -21,7 +21,7 @@ jobs:
         os: [ubuntu-latest, macos-latest, windows-latest]
         emacs-version:
           - 28.2
-          - 29.2
+          - 29.3
         experimental: [false]
         include:
         - os: ubuntu-latest