Bump actions/checkout from 5 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 5 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v5...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/checkers.yml

@@ -12,7 +12,7 @@ jobs:
   linkcheck:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - uses: JustinBeckwith/linkinator-action@v2
       with:
         linksToSkip: '^https://github.com/ ^https://www.jwz.org/ ^https://www.npmjs.com/ ^https://opensource.org/ ^https://unix.stackexchange.com/'
@@ -21,7 +21,7 @@ jobs:
   spellcheck:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - uses: tbroadley/spellchecker-cli-action@v1
       with:
         dictionaries: '.github/dictionary.txt'

.github/workflows/ci.yml

@@ -20,7 +20,7 @@ jobs:
         node-version: [ 20, 22, 24 ]
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Use Node.js ${{ matrix.node-version }}
       uses: actions/setup-node@v6
       with:
@@ -34,7 +34,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Use pnpm latest
       uses: pnpm/action-setup@v4
       with:

.github/workflows/codeql-analysis.yml

@@ -21,7 +21,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
 
     - name: Initialize CodeQL
       uses: github/codeql-action/init@v4

.github/workflows/test-repos.yml

@@ -18,7 +18,7 @@ jobs:
         node-version: [ latest ]
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Use Node.js ${{ matrix.node-version }}
       uses: actions/setup-node@v6
       with:

.github/workflows/update-test-repos.yml

@@ -15,7 +15,7 @@ jobs:
       pull-requests: write
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
       with:
         ref: next
     - uses: actions/setup-node@v6