Bump OSX tests

Author: Baltoli

.github/workflows/test.yml

@@ -79,7 +79,7 @@ jobs:
             os: ubuntu-22.04
             nix: x86_64-linux
           - runner: MacM1
-            os: self-macos-12
+            os: self-macos-14
             nix: aarch64-darwin
     runs-on: ${{ matrix.runner }}
     steps: