Attempt a binary wheel of lxml in combination with {macos, py3.10}

.github/workflows/unittests.yaml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       matrix:
         os: [macos-latest]
-        python-version: ["3.10.0-alpha.1"]
+        python-version: ["3.10"]
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v3
@@ -24,6 +24,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
+          pip install --only-binary=lxml lxml
           pip install -r requirements-dev.txt
       - name: Unittest and Coverage Report
         run: |