Update build.yml

Author: rob-bygrave

.github/workflows/build.yml

@@ -17,14 +17,14 @@ jobs:
         os: [ubuntu-latest]
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Set up Java
       uses: actions/setup-java@v2
       with:
         java-version: ${{ matrix.java_version }}
         distribution: 'zulu'
     - name: Maven cache
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       env:
         cache-name: maven-cache
       with: