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](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] <[email protected]>

Author: dependabot[bot]

.github/workflows/deploy-docker-image-main.yml

@@ -17,7 +17,7 @@ jobs:
     environment: dockerhub
     steps:
       - name: Check out the repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Login to Docker Hub
         uses: docker/login-action@v3

.github/workflows/deploy-docker-image-release.yml

@@ -12,7 +12,7 @@ jobs:
     environment: dockerhub
     steps:
       - name: Check out the repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Extract tag name
         id: extract_tag

.github/workflows/docker-image-ci.yml

@@ -19,7 +19,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out the repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Build the Docker image
         run: |

.github/workflows/dockerfile-lint.yml

@@ -14,7 +14,7 @@ jobs:
   dockerfile-lint:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Run Dockerfile lint
       # https://github.com/hadolint/hadolint
       # TODO: find better alternatives?

.github/workflows/toolkit-updater.yaml

@@ -11,7 +11,7 @@ jobs:
 
     steps:
       - name: Checkout Repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v6