Bump actions/checkout from 2 to 3 (#903)

Bumps [actions/checkout](https://github.com/actions/checkout) from 2 to 3.
- [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...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/ci.yaml

@@ -19,7 +19,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Check out code from Github
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
 
     - name: Set up Python ${{ env.DEFAULT_PYTHON }}
       id: python
@@ -78,7 +78,7 @@ jobs:
             plex: claimed
     steps:
     - name: Check out code from Github
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
 
     - name: Set up Python ${{ matrix.python-version }}
       id: python
@@ -214,7 +214,7 @@ jobs:
             plex: claimed
     steps:
     - name: Check out code from GitHub
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
 
     - name: Set up Python ${{ env.DEFAULT_PYTHON }}
       id: python

.github/workflows/pypi.yml

@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Checkout code
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
 
     - name: Set up Python
       uses: actions/setup-python@v2