ci: fix syntax

Author: avsm

.github/workflows/ci.yml

@@ -19,7 +19,7 @@ jobs:
         uses: astral-sh/setup-uv@v6
         with:
           enable-cache: true
-          python-version: {{ matrix.python-version }}
+          python-version: ${{ matrix.python-version }}
 
       - name: Build
         run: uv sync --locked --all-extras --dev