Bump actions/checkout from 5 to 6

Bumps [actions/checkout](https://github.com/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
...

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

Author: dependabot[bot]

.github/workflows/release-build.yml

@@ -14,7 +14,7 @@ jobs:
       TAG: ${{ github.ref_name }}
       GH_TOKEN: ${{ github.token }}
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Build executable
         run: |
           swift build \
@@ -46,7 +46,7 @@ jobs:
       SHA256: ${{ needs.release-build.outputs.sha }}
     steps:
       - name: Checkout FelixHerrmann/homebrew-tap
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           repository: 'FelixHerrmann/homebrew-tap'
       - name: Update Formula

.github/workflows/swiftlint.yml

@@ -24,7 +24,7 @@ jobs:
     name: SwiftLint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: norio-nomura/action-swiftlint@3.2.1
         with:
           args: --strict

.github/workflows/xcodebuild.yml

@@ -37,7 +37,7 @@ jobs:
       - uses: maxim-lobanov/setup-xcode@v1
         with:
           xcode-version: latest-stable
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Build Scheme
         run: |
           xcodebuild \
@@ -52,7 +52,7 @@ jobs:
       - uses: maxim-lobanov/setup-xcode@v1
         with:
           xcode-version: latest-stable
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install Tuist
         run: brew install tuist
       - name: Run tests