Update actions/checkout to version 6 in CI workflows

Author: ahosgood

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
       matrix:
         python-version: ["3.14", "3.13", "3.12", "3.11", "3.10"]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v5
         with:

.github/workflows/deploy-docs.yml

@@ -27,7 +27,7 @@ jobs:
       url: ${{ steps.deployment.outputs.page_url }}
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: Build documentation
         run: docker run -v ${PWD}:/docs squidfunk/mkdocs-material build
       - name: Setup Pages

.github/workflows/publish.yml

@@ -16,7 +16,7 @@ jobs:
       matrix:
         python-version: ["3.14", "3.13", "3.12", "3.11", "3.10"]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v5
         with:
@@ -34,9 +34,11 @@ jobs:
     permissions:
       id-token: write
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: Set up Python
         uses: actions/setup-python@v5
+        with:
+          python-version: "3.14"
       - name: Install build dependencies
         run: |
           python -m pip install --upgrade pip