Bump actions/checkout from 2.4.0 to 3 (#521)

Bumps [actions/checkout](https://github.com/actions/checkout) from 2.4.0 to 3.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v2.4.0...v3)

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

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/main.yml

@@ -16,7 +16,7 @@ jobs:
       id: go
 
     - name: Check out code into the Go module directory
-      uses: actions/checkout@v2.4.0
+      uses: actions/checkout@v3
 
     - name: Cache modules
       uses: actions/[email protected]