Bump actions/checkout from 3 to 4

Bumps [actions/checkout](https://github.com/actions/checkout) from 3 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v3...v4)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/changelog-validation.yml

@@ -9,7 +9,7 @@ jobs:
   verify-json-validation:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Validate JSON
         uses: docker://orrosenblatt/validate-json-action:latest
         env:

.github/workflows/snippet-generation-pr.yml

@@ -22,7 +22,7 @@ jobs:
     runs-on: ubuntu-latest # https://github.com/actions/virtual-environments/blob/master/images/linux/Ubuntu1804-README.md
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
       with:
         fetch-depth: 10 # number of commits to fetch so that we can query history