Bump actions/checkout from 4 to 5

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 5.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...v5)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/main.yaml

@@ -21,7 +21,7 @@ jobs:
       image: ghcr.io/elementary/docker:${{ matrix.version }}
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Install Dependencies
         run: |
           apt update

.github/workflows/release.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     if: github.event.pull_request.merged == true && true == contains(join(github.event.pull_request.labels.*.name), 'Release')
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - uses: elementary/actions/release@main
         env:
           GIT_USER_TOKEN: "${{ secrets.GIT_USER_TOKEN }}"