Test on Apple Silicon (#203)

Author: odow

.github/workflows/ci.yml

@@ -11,9 +11,13 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        version: ['1']
+        version: ['1.6', '1']
         os: [ubuntu-latest, macOS-latest, windows-latest]
         arch: [x64]
+        include:
+         - version: '1'
+           os: macos-14
+           arch: aarch64
         # HiGHS segfaults on 32-bit.
         # Upstream is https://github.com/ERGO-Code/HiGHS/issues/769
         # but we decided investigating was a low priority until it