Bump actions/checkout from 4 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...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] <[email protected]>

Author: dependabot[bot]

.github/workflows/docs.yml

@@ -15,7 +15,7 @@ jobs:
         run: |
           python --version
       - name: Clone Git repository (without depth limitation)
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
       - name: Install dependencies

.github/workflows/publish.yml

@@ -7,7 +7,7 @@ jobs:
     name: Build distribution
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
       with:
         submodules: true
     - name: Install uv

.github/workflows/python-versions.yml

@@ -22,7 +22,7 @@ jobs:
         run: |
           python --version
       - name: Clone Git repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           path: git-repo
       - name: Install Python package

.github/workflows/sounddevice-data.yml

@@ -27,7 +27,7 @@ jobs:
         run: |
           python --version
       - name: Clone Git repository (with submodules)
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           path: git-repo
           submodules: true

.github/workflows/static-analyzers.yml

@@ -12,7 +12,7 @@ jobs:
         run: |
           python --version
       - name: Clone Git repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: Install sounddevice module
         run: |
           python -m pip install .