Update actions/checkout action to v3 (#110)

Co-authored-by: Renovate Bot <[email protected]>

Author: renovate[bot]

.github/workflows/ci.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
       - name: Set up JDK 8
         uses: actions/setup-java@v3

.github/workflows/release.yml

@@ -44,7 +44,7 @@ jobs:
           java-version: 8
 
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
         with:
           token: ${{ secrets.REPO_ACCESS_TOKEN }}