Bump actions/checkout from 3 to 4

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]>

.github/workflows/ci.yml

@@ -32,21 +32,21 @@ jobs:
       CODECOV_TOKEN: 'dc94d508-39d3-4369-b1c6-321749f96f7c'
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           # Work around a codecov issue detecting commit SHAs
           # see: https://community.codecov.io/t/issue-detecting-commit-sha-please-run-actions-checkout-with-fetch-depth-1-or-set-to-0/2571
           fetch-depth: 0
 
       - name: Checkout OpenShotAudio
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: OpenShot/libopenshot-audio
           path: audio
 
       - name: Checkout Resvg
         if: ${{ matrix.compiler.cc == 'clang' && runner.os == 'linux' }}
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: RazrFalcon/resvg
           path: resvg

.github/workflows/reuse.yml

@@ -23,6 +23,6 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: REUSE Compliance Check
         uses: fsfe/[email protected]