ci: migrate api-check workflow to use uv instead of pip

The griffe API check was failing due to pip install issues. This commit updates
the workflow to use uv for dependency management, which is already used in the
main test workflow.

Changes:
- Added astral-sh/setup-uv@v6 action to install uv
- Replaced 'pip install' commands with 'uv sync --group test' and 'uv pip install griffe'
- Updated griffe command to use 'uv run griffe' for proper environment execution

This ensures consistent dependency resolution and fixes the installation failures.

Author: RonnyPfannschmidt

.github/workflows/api-check.yml

@@ -28,18 +28,20 @@ jobs:
         with:
           python-version: '3.11'
 
+      - name: Install the latest version of uv
+        uses: astral-sh/setup-uv@v6
+
       - name: Install dependencies
         run: |
-          pip install -U pip setuptools
-          pip install -e .[test]
-          pip install griffe
+          uv sync --group test
+          uv pip install griffe
 
       - name: Run griffe API check
         id: griffe-check
         continue-on-error: true
         run: |
           echo "Running griffe API stability check..."
-          if griffe check setuptools_scm -ssrc -f github; then
+          if uv run griffe check setuptools_scm -ssrc -f github; then
             echo "api_check_result=success" >> $GITHUB_OUTPUT
             echo "exit_code=0" >> $GITHUB_OUTPUT
           else