Bump actions/checkout from 2 to 3.1.0

Bumps [actions/checkout](https://github.com/actions/checkout) from 2 to 3.1.0.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v2...v3.1.0)

---
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/ci.yml

@@ -19,7 +19,7 @@ jobs:
         with:
           go-version: ${{ matrix.go-version }}
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3.1.0
       - name: Build
         run: go build -v .
       - name: Test
@@ -38,7 +38,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3.1.0
       - name: goreleaser
         if: success()
         uses: docker://goreleaser/goreleaser:latest