build: Upgrade to checkout action v3

Author: Julien Ruaux

.github/workflows/build.yml

@@ -10,7 +10,7 @@ jobs:
     if: startsWith(github.event.head_commit.message, 'Releasing version') != true
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
       - name: Set up Java
         uses: actions/setup-java@v1

.github/workflows/publish.yml

@@ -11,7 +11,7 @@ jobs:
     name: Release
     runs-on: ubuntu-18.04
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           fetch-depth: 0