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] <support@github.com>

Author: dependabot[bot]

.github/workflows/integration-tests-sqlserver.yml

@@ -64,7 +64,7 @@ jobs:
           DBT_TEST_USER_3: DBT_TEST_USER_3
           COLLATION: ${{ matrix.collation }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install uv
         run: pip install uv

.github/workflows/publish-docker.yml

@@ -20,7 +20,7 @@ jobs:
       packages: write
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Log in to the Container registry
         uses: docker/login-action@v3.3.0
@@ -50,7 +50,7 @@ jobs:
       packages: write
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Log in to the Container registry
         uses: docker/login-action@v3.3.0

.github/workflows/release-version.yml

@@ -11,7 +11,7 @@ jobs:
     name: Release new version
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - uses: actions/setup-python@v5
         with:

.github/workflows/unit-tests.yml

@@ -30,7 +30,7 @@ jobs:
         password: ${{ secrets.github_token }}
     steps:
 
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install uv
         run: pip install uv