Bump actions/checkout from 5 to 6 (#48)

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

Author: dependabot[bot]

.github/workflows/auto-merge.yaml

@@ -13,7 +13,7 @@ jobs:
       - name: Dependabot metadata
         id: dependabot-metadata
         uses: dependabot/fetch-metadata@v2
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Setup gh cli
         uses: ksivamuthu/actions-setup-gh-cli@v3
       - name: Approve a Dependabot PR

.github/workflows/golangci-lint.yml

@@ -13,7 +13,7 @@ jobs:
     name: lint
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - uses: actions/setup-go@v6
       with:
         go-version-file: go.mod

.github/workflows/ubuntu.yml

@@ -15,7 +15,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
 
     - name: Set up Go
       uses: actions/setup-go@v6