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] <[email protected]>

Author: dependabot[bot]

.github/workflows/cicd-1-pull-request.yaml

@@ -25,7 +25,7 @@ jobs:
       does_pull_request_exist: ${{ steps.pr_exists.outputs.does_pull_request_exist }}
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: "Set CI/CD variables"
         id: variables
         run: |

.github/workflows/stage-1-commit.yaml

@@ -35,7 +35,7 @@ jobs:
     timeout-minutes: 2
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0 # Full history is needed to scan all commits
       - name: "Scan secrets"
@@ -46,7 +46,7 @@ jobs:
     timeout-minutes: 2
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0 # Full history is needed to compare branches
       - name: "Check file format"
@@ -57,7 +57,7 @@ jobs:
     timeout-minutes: 2
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0 # Full history is needed to compare branches
       - name: "Check Markdown format"
@@ -68,7 +68,7 @@ jobs:
     timeout-minutes: 2
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0 # Full history is needed to compare branches
       - name: "Check English usage"
@@ -82,7 +82,7 @@ jobs:
     timeout-minutes: 2
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: "Count lines of code"
         uses: ./.github/actions/create-lines-of-code-report
         with:
@@ -101,7 +101,7 @@ jobs:
     timeout-minutes: 2
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: "Scan dependencies"
         uses: ./.github/actions/scan-dependencies
         with:

.github/workflows/stage-2-test.yaml

@@ -35,6 +35,6 @@ jobs:
     timeout-minutes: 3
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: "Run Playwright Tests"
         uses: ./.github/actions/run-playwright-tests