chore(deps): update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/actionlint.yml

@@ -15,7 +15,7 @@ jobs:
     timeout-minutes: 15
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Download actionlint
         id: get_actionlint
         run: bash <(curl https://raw.githubusercontent.com/rhysd/actionlint/main/scripts/download-actionlint.bash)

.github/workflows/bashate.yml

@@ -15,7 +15,7 @@ jobs:
     timeout-minutes: 15
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: actions/setup-python@v6
         with:
           python-version: 3.14

.github/workflows/checkmake.yml

@@ -15,5 +15,5 @@ jobs:
     timeout-minutes: 15
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: Uno-Takashi/checkmake-action@v2

.github/workflows/copyrights.yml

@@ -15,7 +15,7 @@ jobs:
     timeout-minutes: 15
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: yegor256/[email protected]
         with:
           globs: >-

.github/workflows/fief.yml

@@ -14,7 +14,7 @@ jobs:
     timeout-minutes: 15
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: 3.4.7

.github/workflows/make.yml

@@ -18,7 +18,7 @@ jobs:
     timeout-minutes: 15
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: actions/setup-java@v5
         with:
           distribution: 'temurin'

.github/workflows/markdown-lint.yml

@@ -15,5 +15,5 @@ jobs:
     timeout-minutes: 15
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: DavidAnson/[email protected]

.github/workflows/pages.yml

@@ -15,7 +15,7 @@ jobs:
     timeout-minutes: 15
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - run: |
           mkdir -p data
           find objects -name '*.eo' > data/objectionary.lst

.github/workflows/pdd.yml

@@ -15,7 +15,7 @@ jobs:
     timeout-minutes: 15
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: volodya-lombrozo/pdd-action@master
       - run: sudo apt-get update --yes --fix-missing && sudo apt-get install --yes ruby-dev libmagic-dev zlib1g-dev
       - uses: ruby/setup-ruby@v1

.github/workflows/python-lint.yml

@@ -15,7 +15,7 @@ jobs:
     timeout-minutes: 15
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Set up Python 3.12
         uses: actions/setup-python@v6
         with: