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](actions/checkout@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/alpine-test.yml

@@ -26,7 +26,7 @@ jobs:
         adduser runner docker
       shell: sh -exo pipefail {0}  # Run this as root, not the "runner" user.
 
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0
 

.github/workflows/codeql.yml

@@ -47,7 +47,7 @@ jobs:
         # your codebase is analyzed, see https://docs.github.com/en/code-security/code-scanning/creating-an-advanced-setup-for-code-scanning/codeql-code-scanning-for-compiled-languages
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
 
     # Add any setup steps before running the `github/codeql-action/init` action.
     # This includes steps like installing compilers or runtimes (`actions/setup-node`

.github/workflows/cygwin-test.yml

@@ -34,7 +34,7 @@ jobs:
         git config --global core.autocrlf false  # Affects the non-Cygwin git.
       shell: pwsh  # Do this outside Cygwin, to affect actions/checkout.
 
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0
 

.github/workflows/lint.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
 
     - uses: actions/setup-python@v6
       with:

.github/workflows/pythonpackage.yml

@@ -39,7 +39,7 @@ jobs:
         shell: bash --noprofile --norc -exo pipefail {0}
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0