deps(actions): bump actions/checkout from 4 to 6

.github/workflows/actionlint.yml

@@ -24,7 +24,7 @@ jobs:
     permissions:
       contents: read
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Run actionlint
         uses: rhysd/[email protected]

.github/workflows/ci.yml

@@ -38,7 +38,7 @@ jobs:
     env:
       PYTHONPATH: src
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v5
@@ -111,7 +111,7 @@ jobs:
       contents: read
       security-events: write
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v5

.github/workflows/codeql.yml

@@ -36,7 +36,7 @@ jobs:
       matrix:
         language: ["python"]
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       # Database must be initialized before dependency install (advanced setup).
       - name: Initialize CodeQL

.github/workflows/docs-audit.yml

@@ -37,7 +37,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 10
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v5

.github/workflows/supply-chain-audit.yml

@@ -23,7 +23,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 30
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install uv
         uses: astral-sh/setup-uv@v5
@@ -56,7 +56,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 45
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install uv
         uses: astral-sh/setup-uv@v5