Bump actions/checkout from 3 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 3 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v3...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/codeql-analysis.yml

@@ -24,7 +24,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v4
+      uses: actions/checkout@v6
 
     - name: Setup Go
       uses: actions/setup-go@v5

.github/workflows/external-message.yml

@@ -21,7 +21,7 @@ jobs:
       pull-requests: write
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Delete old comments
         env:

.github/workflows/integration-tests.yml

@@ -43,7 +43,7 @@ jobs:
     environment: "test-trigger-is"
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v6
 
     - name: Generate GitHub App Token for Workflow Trigger
       id: generate-token

.github/workflows/next-changelog.yml

@@ -13,7 +13,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v6
 
       - name: Fetch list of changed files
         id: changed-files

.github/workflows/push.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup Go
         uses: actions/setup-go@v5
@@ -34,7 +34,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup Go
         uses: actions/setup-go@v5

.github/workflows/release.yml

@@ -15,7 +15,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
 

.github/workflows/schema.yml

@@ -24,21 +24,21 @@ jobs:
       # uses the current commit as the head commit.
       - if: github.event_name == 'pull_request'
         name: Checkout PR base commit
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           ref: ${{ github.base_ref }}
       - if: github.event_name == 'pull_request'
         name: Checkout PR merge commit
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - if: github.event_name == 'workflow_dispatch'
         name: Checkout base commit
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           ref: ${{ github.event.inputs.base }}
       - if: github.event_name == 'workflow_dispatch'
         name: Checkout head commit
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           ref: ${{ github.event.inputs.head }}
 

.github/workflows/validate-sha.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Validate SHA
         run: |