Bump actions/checkout from 2.4.0 to 3.0.2

Bumps [actions/checkout](https://github.com/actions/checkout) from 2.4.0 to 3.0.2.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v2.4.0...v3.0.2)

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

Signed-off-by: dependabot[bot] <support@github.com>

Closes #27

Change-Id: I1464097c9d4160fbe73cfd8ef9f2e8653945d1b9
diff --git a/.github/workflows/pythonpackage.yml b/.github/workflows/pythonpackage.yml
index f007610..96efb4e 100644
--- a/.github/workflows/pythonpackage.yml
+++ b/.github/workflows/pythonpackage.yml
@@ -14,7 +14,7 @@
         r-version: [release]
         os: [windows-latest, macOS-latest, ubuntu-latest]
     steps:
-    - uses: actions/checkout@v2.4.0
+    - uses: actions/checkout@v3.0.2
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v4.2.0
       with: