Bump actions/checkout from 2.4.0 to 3.2.0

Bumps [actions/checkout](https://github.com/actions/checkout) from 2.4.0 to 3.2.0.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v2.4.0...v3.2.0)

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

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -25,7 +25,7 @@ jobs:
       fail-fast: false
     steps:
       - name: Checkout
-        uses: actions/checkout@v2.4.0
+        uses: actions/checkout@v3.2.0
         with:
           fetch-depth: 0
       - name: Setup .NET SDK

.github/workflows/run-markdownsnippets.yml

@@ -10,7 +10,7 @@ jobs:
     name: Process documentation
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3.2.0
     - name: Run MarkdownSnippets
       run: |
         dotnet tool install --global MarkdownSnippets.Tool