Bump actions/checkout from 5 to 6 in /.github/workflows

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/docker-security.yml

@@ -19,7 +19,7 @@ jobs:
 
     steps:
       - name: 🧾 Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: 🔨 Build Docker Image
         run: |
@@ -113,7 +113,7 @@ jobs:
 
     steps:
       - name: 🧾 Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: 🔍 Run Hadolint (Dockerfile Linter)
         uses: hadolint/[email protected]
@@ -167,7 +167,7 @@ jobs:
 
     steps:
       - name: 🧾 Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: 🔨 Build Docker Image
         run: |

.github/workflows/tests.yml

@@ -8,7 +8,7 @@ jobs:
 
     steps:
       - name: 🧾 Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: ⚙️ Setup BATS
         run: ./setup-bats.sh