ci: CuPy 14 + Python 3.14 (#2352)

Author: flying-sheep

.github/workflows/test-gpu.yml

@@ -52,24 +52,19 @@ jobs:
       - name: Nvidia SMI sanity check
         run: nvidia-smi
 
-      - name: Install yq # https://cirun.slack.com/archives/C09SNDRB3A8/p1766512487317849?thread_ts=1766512112.938459&cid=C09SNDRB3A8
-        # https://github.com/mikefarah/yq/issues/2592 forces version pin
-        run: |
-          sudo wget -qO /usr/local/bin/yq https://github.com/mikefarah/yq/releases/download/v4.49.2/yq_linux_amd64
-          sudo chmod +x /usr/local/bin/yq
-
-      - name: Extract max Python version from classifiers
-        run: |
-          classifiers=$(yq .project.classifiers pyproject.toml -oy  | grep --only-matching --perl-regexp '(?<=Python :: )(\d\.\d+)')
-          max_version=$(echo "$classifiers" | sort -V | tail -1)
-          echo "max_python_version=$max_version" >> $GITHUB_ENV
-
       - name: Install UV
         uses: astral-sh/setup-uv@v6 # TODO: upgrade once cirun image supports node 24
         with:
           enable-cache: true
-          # Any Cuda 14+ will support Python 3.14: https://github.com/cupy/cupy/issues/9346
-          python-version: '3.13'  # ${{ env.max_python_version }}
+
+      - name: Extract max Python version from classifiers
+        run: |
+          import os
+          import check_python_versions.sources.pyproject as cpv
+          *_, max_ver = cpv.get_supported_python_versions()
+          with open(os.environ["GITHUB_ENV"], "a") as env:
+            print(f"UV_PYTHON={max_ver}", file=env)
+        shell: uvx --with=check-python-versions==0.24 python {0}
 
       - name: Install AnnData
         run: |