build(deps): 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] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -15,7 +15,7 @@ jobs:
         node-version: ['18', '20']
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - uses: pnpm/action-setup@v4
         with:

.github/workflows/plan-release.yml

@@ -21,7 +21,7 @@ jobs:
       command: ${{ steps.check-release.outputs.command }}
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0
           ref: 'main'
@@ -46,7 +46,7 @@ jobs:
     if: (github.event_name == 'push' && needs.check-plan.outputs.command != 'release') || (github.event_name == 'pull_request_target' && github.event.pull_request.merged == true)
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         # We need to download lots of history so that
         # github-changelog can discover what's changed since the last release
         with:

.github/workflows/publish.yml

@@ -23,7 +23,7 @@ jobs:
       command: ${{ steps.check-release.outputs.command }}
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0
           ref: 'main'
@@ -43,7 +43,7 @@ jobs:
       pull-requests: write
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: actions/setup-node@v4
         with:
           node-version: 18