Bump actions/checkout from 2 to 4

Bumps [actions/checkout](https://github.com/actions/checkout) from 2 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v2...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>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -31,7 +31,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out the repo
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
       - # https://github.com/marketplace/actions/build-and-push-docker-images
         name: Prepare tags
         id: prep

.github/workflows/linter.yml

@@ -37,7 +37,7 @@ jobs:
       # Checkout the code base #
       ##########################
       - name: Checkout Code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       ################################
       # Run Linter against code base #