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>

.github/workflows/fossa.yaml

@@ -11,7 +11,7 @@ jobs:
     if: github.repository_owner == 'uber-go'
     steps:
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: FOSSA analysis
         uses: fossas/fossa-action@v1

.github/workflows/go.yml

@@ -28,7 +28,7 @@ jobs:
         go-version: ${{ matrix.go }}
 
     - name: Checkout code
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
 
     - name: Load cached dependencies
       uses: actions/cache@v1