ci: build the x86_64 macOS wheel on the Apple-Silicon runner (#4)

GitHub's Intel macos-13 runner pool is deprecated and now queues for
hours, so the x86_64-apple-darwin wheel job never started and publish —
which needs the whole build matrix — stalled the entire Release, which
in turn left PyPI (and the downstream AUR bump) without the new version.
Cross-compile the Intel wheel on macos-14; maturin adds the target and
produces the x86_64 wheel with no Intel host required.

Author: jqueguiner

.github/workflows/release.yml

@@ -45,7 +45,10 @@ jobs:
       matrix:
         platform:
           - { os: macos-14,       target: aarch64-apple-darwin }
-          - { os: macos-13,       target: x86_64-apple-darwin }
+          # Cross-compile the Intel wheel on the Apple-Silicon runner:
+          # GitHub's macos-13 (Intel) pool is deprecated and queues for hours,
+          # which stalled the whole Release (publish needs every build job).
+          - { os: macos-14,       target: x86_64-apple-darwin }
           - { os: ubuntu-latest,  target: x86_64-unknown-linux-gnu,  manylinux: auto }
           - { os: ubuntu-latest,  target: aarch64-unknown-linux-gnu, manylinux: auto }
           - { os: windows-latest, target: x86_64-pc-windows-msvc }