build(deps): 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/build-and-cache-libpq.yml

@@ -64,7 +64,7 @@ jobs:
         platform: [manylinux, musllinux]
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - name: Set up QEMU for multi-arch build
         # Check https://github.com/docker/setup-qemu-action for newer versions.
@@ -114,7 +114,7 @@ jobs:
 
     steps:
       - name: Checkout repos
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Cache libpq build
         uses: actions/cache@v4

.github/workflows/packages.yml

@@ -30,7 +30,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repos
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Build sdist
         run: ./scripts/build/build_sdist.sh
@@ -80,7 +80,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repos
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set up QEMU for multi-arch build
         uses: docker/setup-qemu-action@v3
@@ -155,7 +155,7 @@ jobs:
 
     steps:
       - name: Checkout repos
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Cache libpq build
         uses: actions/cache@v4
@@ -209,7 +209,7 @@ jobs:
         run: rm -rf c:/tools/php C:/Strawberry/c/bin
 
       - name: Checkout repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Start PostgreSQL service for test
         run: |

.github/workflows/tests.yml

@@ -52,7 +52,7 @@ jobs:
           --health-retries 5
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       # Can enable to test an unreleased libpq version.
       - name: install libpq 16