Bump actions/checkout from 2 to 3 (#301)

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](actions/checkout@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>

Author: dependabot[bot]

.github/workflows/main.yml

@@ -17,7 +17,7 @@ jobs:
       version: ${{ steps.version.outputs.version }}
       prerelease: ${{ steps.version.outputs.prerelease }}
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
       with:
         fetch-depth: 0
     - uses: actions/setup-python@v3
@@ -58,7 +58,7 @@ jobs:
         python-version: ['3.7', '3.8', '3.9', '3.10']
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
       with:
         fetch-depth: 0
     - uses: actions/setup-python@v3
@@ -103,7 +103,7 @@ jobs:
       run: |
         sudo apt-get install -y pandoc
     - name: Checkout
-      uses: actions/checkout@v2.4.0
+      uses: actions/checkout@v3
       with:
         fetch-depth: 0
     - name: Download distributions