Use MacOS 14 CI Runners

MacOS 12 runners are deprecated [1] so we need to use MacOS 14. By
default MacOS 14 runners are ARM based but we can use the MacOS 14 large
runners which are still Intel based.

[1]: actions/runner-images#10721
[2]: https://github.com/actions/runner-images

.github/workflows/test.yml

@@ -12,14 +12,13 @@ jobs:
         job:
           # Operating systems available: https://docs.github.com/en/actions/using-github-hosted-runners/about-github-hosted-runners/about-github-hosted-runners#standard-github-hosted-runners-for-public-repositories
           - { target: x86_64-unknown-linux-gnu, os: ubuntu-20.04 }
-          # mac-latest (currently mac-14) is an ARM device, so use macos-12 to get Intel.
-          # Update annoucement: https://github.blog/changelog/2024-04-01-macos-14-sonoma-is-generally-available-and-the-latest-macos-runner-image/
-          - { target: x86_64-apple-darwin, os: macos-12 }
           - { target: x86_64-pc-windows-msvc, os: windows-latest }
 
           - { target: aarch64-unknown-linux-gnu, os: ubuntu-20.04, use-cross: true }
 
-          # mac-14 is an M1 ARM device.
+          # macos-14 is an M1 ARM device but macos-14 is x86-64
+          # https://github.com/actions/runner-images
+          - { target: x86_64-apple-darwin, os: macos-14-large }
           - { target: aarch64-apple-darwin, os: macos-14 }
 
           # musl binaries produced by GitHub actions segfault when run, see