Fix CI (set up uv)

Author: davisagli

.github/workflows/test.yml

@@ -9,15 +9,11 @@ jobs:
     steps:
       - uses: actions/checkout@v7
 
-      - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v6
-        with:
-          python-version: "3.12"
+      - name: Install uv
+        uses: astral-sh/setup-uv@v9.0.0
 
       - name: Install dependencies
         run: |
-          python -m pip install --upgrade pip
-          pip install -q -r requirements.txt -c constraints.txt
           sudo snap install --edge vale
 
       - name: Run tests with make test (includes clean and linkcheckbroken)