Bump actions/checkout in the github-actions group across 1 directory

Bumps the github-actions group with 1 update in the / directory: [actions/checkout](https://github.com/actions/checkout).


Updates `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
  dependency-group: github-actions
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/check-build.yml

@@ -20,7 +20,7 @@ jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install dependencies
         run: npm ci
       - name: Build

.github/workflows/deploy-preview-with-version.yml

@@ -22,7 +22,7 @@ jobs:
     permissions:
       checks: write
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Deploy to Firebase Hosting preview channel
         id: firebase_hosting_preview
         uses: ./

.github/workflows/deploy-preview.yml

@@ -22,7 +22,7 @@ jobs:
     permissions:
       checks: write
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Deploy to Firebase Hosting preview channel
         id: firebase_hosting_preview
         uses: ./

.github/workflows/deploy-production.yml

@@ -9,7 +9,7 @@ jobs:
   deploy_website:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       # - run: npm run build
       - uses: ./
         with:

.github/workflows/test.yml

@@ -20,7 +20,7 @@ jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install dependencies
         run: npm ci
       - name: Check that Prettier was run