Bump actions/checkout from 2 to 3 (#137)

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>

.github/workflows/hassfest.yaml

@@ -11,5 +11,5 @@ jobs:
   validate:
     runs-on: "ubuntu-latest"
     steps:
-      - uses: "actions/checkout@v2"
+      - uses: "actions/checkout@v3"
       - uses: home-assistant/actions/hassfest@master

.github/workflows/release.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repo
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
 
       - name: Set up Python
         uses: actions/setup-python@v4