GH CI: add separate flow for MacOS aarch64 (#3669)

Co-authored-by: ikappaki <[email protected]>

Author: ikappaki

.github/workflows/test.yml

@@ -21,9 +21,17 @@ jobs:
 
     strategy:
       matrix:
-        os: [macos-latest, ubuntu-latest, windows-latest]
-        emacs_version: ['26.3', '27.2', '28.2', '29.1']
+        os: [macos-13, ubuntu-latest, windows-latest]
+        emacs_version: ['26.3', '27.2', '28.2', '29.3']
         java_version: ['11', '17']
+        include:
+          # aarch64 (macos-13 is Intel)
+          - os: macos-latest
+            emacs_version: '29.3'
+            java_version: '11'
+          - os: macos-latest
+            emacs_version: '28.2'
+            java_version: '11'
 
     steps:
     - name: Set up Emacs