Bump actions/checkout from 3 to 4 (#208)

Bumps [actions/checkout](https://github.com/actions/checkout) from 3 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v3...v4)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/auto-merge.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     if: github.actor == 'dependabot[bot]'
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: ahmadnassri/[email protected]
         with:
           github-token: ${{ secrets.AUTOMERGE_TOKEN }}

.github/workflows/links.yml

@@ -10,7 +10,7 @@ jobs:
   linkChecker:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Link Checker
         uses: ./ # Uses an action in the root directory

.github/workflows/test.yml

@@ -11,7 +11,7 @@ jobs:
     name: Test the lychee link checker action
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: test defaults
         uses: ./

.github/workflows/test_cache.yml

@@ -17,7 +17,7 @@ jobs:
           key: cache-lychee-${{ github.sha }}
           restore-keys: cache-lychee-
 
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Lychee URL checker
         uses: lycheeverse/lychee-action@v1