Add release job to publish macOS arm64 binaries

With the recent release of cibuildwheel 1.9.0 support for building arm64
binaries on macOS was added. This enables us to build release binaries
for this new platform. However, these binaries will be cross-compiled
and not tested since there are no CI resources with the platform
available. This commit adds a new release wheel job to build a aarch64
binary and publish an arm64 wheel for macOS. This will enable users who
have an arm64 mac to run retworkx without having to either build from
source or run under rosetta 2.

Fixes Qiskit#231

.github/workflows/wheels.yml

@@ -1,5 +1,6 @@
 ---
 name: Wheel Builds
+
 on:
   push:
     tags:
@@ -44,7 +45,7 @@ jobs:
           toolchain: stable
       - name: Install cibuildwheel
         run: |
-          python -m pip install cibuildwheel==1.6.3 twine
+          python -m pip install cibuildwheel==1.9.0 twine
       - name: Build wheels
         run: |
           python -m cibuildwheel --output-dir wheelhouse
@@ -57,7 +58,25 @@ jobs:
           CIBW_SKIP: cp27-* cp34-* cp35-* pp* *win32
           CIBW_BEFORE_BUILD: pip install -U setuptools-rust
           CIBW_TEST_COMMAND: python -m unittest discover {project}/tests
-
+      - uses: actions/upload-artifact@v2
+        with:
+          path: ./wheelhouse/*.whl
+      - name: Upload to PyPI
+        run: twine upload ./wheelhouse/*.whl
+        env:
+          TWINE_PASSWORD: ${{ secrets.TWINE_PASSWORD }}
+          TWINE_USERNAME: retworkx-ci
+  build-mac-arm-wheels:
+    name: Build wheels on macos for arm
+    runs-on: macos-10.15
+    steps:
+      - uses: actions/checkout@v2
+      - name: Build wheels
+        uses: joerick/[email protected]
+        env:
+          CIBW_ARCHS_MACOS: arm64
+          CIBW_BEFORE_BUILD: pip install -U setuptools-rust
+          CIBW_ENVIRONMENT: CARGO_BUILD_TARGET="aarch64-apple-darwin"
       - uses: actions/upload-artifact@v2
         with:
           path: ./wheelhouse/*.whl
@@ -85,7 +104,7 @@ jobs:
         run: rustup default stable-i686-pc-windows-msvc
       - name: Install cibuildwheel
         run: |
-          python -m pip install cibuildwheel==1.6.3 twine
+          python -m pip install cibuildwheel==1.9.0 twine
       - name: Build wheels
         run: |
           python -m cibuildwheel --output-dir wheelhouse