Include Python 3.12 in CI coverage

.github/workflows/ci.yml

@@ -31,7 +31,7 @@ jobs:
     strategy:
       fail-fast: ${{ !contains(github.event.pull_request.labels.*.name, 'CI-no-fail-fast') }}
       matrix:
-        python-version: ["3.7", "3.8", "3.9", "3.10", "3.11"]
+        python-version: ["3.7", "3.8", "3.9", "3.10", "3.11", "3.12"]
         platform: [
           { os: "ubuntu-latest", python-architecture: "x64", rust-target: "x86_64-unknown-linux-gnu" },
           { os: "macOS-latest",   python-architecture: "x64", rust-target: "x86_64-apple-darwin" },
@@ -174,10 +174,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
-      - name: Set up Python
-        uses: actions/setup-python@v4
-        with:
-          python-version: 3.8
       - name: Install OpenBLAS
         run: sudo apt install --yes libopenblas-dev
       - name: Install Rust
@@ -195,11 +191,6 @@ jobs:
     needs: [lint, check-msrv, examples]
     steps:
       - uses: actions/checkout@v3
-      - name: Set up Python
-        uses: actions/setup-python@v4
-        with:
-          python-version: 3.9
-          architecture: x64
       - name: Install numpy
         run: pip install numpy ml_dtypes
       - uses: Swatinem/rust-cache@v2