build(deps): 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](https://github.com/actions/checkout/compare/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>

.github/workflows/apidiff.yml

@@ -13,7 +13,7 @@ jobs:
     if: (github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name != github.repository)
     steps:
       - name: Clone the code
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
       - name: Setup Go

.github/workflows/go.yml

@@ -17,7 +17,7 @@ jobs:
     outputs:
       doc: ${{ steps.filter.outputs.doc }}
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - uses: dorny/paths-filter@v3
       id: filter
       with:
@@ -32,7 +32,7 @@ jobs:
     runs-on: [ubuntu-latest]
     steps:
     - name: Check out code into the Go module directory
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
       with:
         fetch-depth: 0
     - name: Set up Go 1.x
@@ -52,7 +52,7 @@ jobs:
     runs-on: [ubuntu-latest]
     steps:
     - name: Check out code into the Go module directory
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
       with:
         fetch-depth: 0
     - name: Set up Go 1.x
@@ -72,7 +72,7 @@ jobs:
     runs-on: [ubuntu-latest]
     steps:
     - name: Check out code into the Go module directory
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
     - name: Set up Go 1.x
       uses: actions/setup-go@v6
       with:
@@ -90,7 +90,7 @@ jobs:
     runs-on: [macos-latest]
     steps:
     - name: Check out code into the Go module directory
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
     - name: Set up Go 1.x
       uses: actions/setup-go@v6
       with:
@@ -108,7 +108,7 @@ jobs:
     runs-on: [windows-latest]
     steps:
     - name: Check out code into the Go module directory
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
     - name: Set up Go 1.x
       uses: actions/setup-go@v6
       with:

.github/workflows/release.yaml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Check out code into the Go module directory
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
       with:
         fetch-depth: 0
     - name: Set up Go 1.x