Bump actions/checkout from 4 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...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] <[email protected]>

Author: dependabot[bot]

.github/workflows/deploy.yml

@@ -14,7 +14,7 @@ jobs:
     if: ${{ ! contains(github.event.head_commit.message, 'autopublish') }}
     steps:
       - name: Checkout this repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           persist-credentials: false
           fetch-depth: 0
@@ -25,7 +25,7 @@ jobs:
 
       - name: Checkout docs website repository
         if: github.event_name == 'push' && github.repository_owner == 'finale-lua'
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           persist-credentials: false
           fetch-depth: 0

.github/workflows/lint.yml

@@ -11,6 +11,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: Luacheck linter
         uses: lunarmodules/luacheck@v1