CI: build universal2 wheels as well

.github/workflows/macOS_universal.yml

@@ -0,0 +1,24 @@
+name: Build
+
+on: [push, pull_request]
+
+jobs:
+  build_wheels:
+    name: Build wheels on ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [macos-13]
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Build wheels
+        uses: pypa/[email protected]
+        env:
+          CIBW_ARCHS: universal2
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: low_index-wheels-${{ matrix.os }}
+          path: ./wheelhouse/*.whl