update action checkout to version 3 (#250)

Author: ddsharpe

.github/workflows/build.yml

@@ -10,7 +10,7 @@ jobs:
     name: Build
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           fetch-depth: 0  # Shallow clones should be disabled for a better relevancy of analysis
       - name: Set up JDK