chore(deps): update actions/setup-python action to v6

Author: renovate[bot]

.github/workflows/cd.yml

@@ -15,7 +15,7 @@ jobs:
     steps:
       - uses: actions/checkout@v6
       - name: Set up Python
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: '3.14'
       - name: Install dependencies

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
     steps:
       - uses: actions/checkout@v6
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: ${{ matrix.python-version }}
       - name: Install