Upgrade macos tests to latest (#7597)

GitHub is deprecating the macos-13 runners.
In fact, we should probably have upgraded much earlier.
https://github.com/actions/runner-images/issues/13046

.github/workflows/ci.yml

@@ -143,7 +143,7 @@ jobs:
             arch: amd64
           - os: ubuntu-22.04-arm
             arch: arm64
-          - os: macos-13
+          - os: macos-latest
             arch: amd64
           - os: macos-latest
             arch: arm64