Bump actions/checkout from 2 to 3

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>

.github/workflows/sync-back-to-dev.yml

@@ -11,7 +11,7 @@ jobs:
     name: Syncing branches
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Opening pull request
         id: pull
         uses: tretuna/sync-branches@1.4.0

.github/workflows/test-and-build.yaml

@@ -17,7 +17,7 @@ jobs:
       DEBIAN_VERSION: buster
     steps:
       - name: Checkout Repo
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Run Tests
         run: |
           echo "Building ${ARCH}-${DEBIAN_VERSION}"
@@ -31,11 +31,11 @@ jobs:
       -
         name: Checkout
         if: github.event_name != 'schedule'
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       -
         name: Checkout dev branch if we are building nightly
         if: github.event_name == 'schedule'
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
         with:
           ref: dev
       -