Add setup-python step and adjust uv install

Introduce actions/setup-python@v5 using matrix.python-version to ensure the correct Python interpreter is available for subsequent steps. Remove the python-version input from the astral-sh/setup-uv step since Python is now configured separately. This clarifies environment setup and avoids duplicating interpreter configuration.

Author: JR-1991

.github/workflows/tests.yml

@@ -14,14 +14,17 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v5
 
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+
       - name: Run Dataverse Action
         id: dataverse
         uses: gdcc/dataverse-action@main
 
       - name: Install uv
         uses: astral-sh/setup-uv@v6
-        with:
-          python-version: ${{ matrix.python-version }}
 
       - name: Install Python Dependencies
         run: |