Bump actions/checkout from 2.4.0 to 3 (#116)

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] <support@github.com>

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

.github/workflows/main.yml

@@ -6,7 +6,7 @@ jobs:
   lint:
     runs-on: ubuntu-20.04
     steps:
-      - uses: actions/checkout@v2.4.0
+      - uses: actions/checkout@v3
       - name: Super-Linter
         uses: github/super-linter@v4.9.0
         env:
@@ -20,7 +20,7 @@ jobs:
       - lint
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2.4.0
+      - uses: actions/checkout@v3
       - name: Setup dotfiles (${{ matrix.os }})
         run: |
           ./setup.sh
@@ -34,7 +34,7 @@ jobs:
       - lint
     runs-on: windows-latest
     steps:
-      - uses: actions/checkout@v2.4.0
+      - uses: actions/checkout@v3
       - name: Setup dotfiles (Windows)
         run: |
           powershell -executionpolicy bypass ".\setup-windows.ps1"