.github: bump actions/checkout from 4 to 5 (#221)

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] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/build-dev-shells.yml

@@ -31,7 +31,7 @@ jobs:
             os: macos-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
       - name: Install Nix
         uses: cachix/install-nix-action@v31
         with:

.github/workflows/check.yml

@@ -11,7 +11,7 @@ jobs:
         arch: [x86_64-linux, aarch64-darwin]
     if: github.ref == 'refs/heads/main'
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Check Nix flake inputs
         uses: DeterminateSystems/flake-checker-action@v12
     # - uses: cachix/install-nix-action@v23

.github/workflows/deadnix.yml

@@ -5,7 +5,7 @@ jobs:
     name: Deadnix
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - uses: cachix/install-nix-action@v31
         with:
           nix_path: nixpkgs=channel:nixos-unstable

.github/workflows/fmt.yml

@@ -5,7 +5,7 @@ jobs:
     name: Check expressions
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - uses: cachix/install-nix-action@v31
         with:
           install_url: https://nixos.org/nix/install

.github/workflows/lint.yml

@@ -5,7 +5,7 @@ jobs:
     name: Lint code
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - uses: cachix/install-nix-action@v31
         with:
           nix_path: nixpkgs=channel:nixos-unstable

.github/workflows/update-flakes.yml

@@ -32,7 +32,7 @@ jobs:
             echo "name=$name"
             echo "email=$id+$name@users.noreply.github.com"
           } >> "$GITHUB_OUTPUT"
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Setup Git
         env:
           GIT_USER_NAME: ${{ steps.user-info.outputs.name || 'github-actions[bot]' }}