Bump actions/checkout from 2 to 3 (#138)

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] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/ci.yaml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: ⤵️ Check out files from GitHub
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Test firmware build
         uses: esphome/[email protected]
         with:

.github/workflows/labels.yaml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: ⤵️ Check out code from GitHub
-        uses: actions/checkout@v2.4.0
+        uses: actions/checkout@v3
       - name: 🚀 Run Label Syncer
         uses: micnncim/[email protected]
         env: