Update build workflow to v4 actions

Author: MattiDragon

.github/workflows/build.yml

@@ -7,9 +7,9 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - name: Set up JDK
-        uses: actions/setup-java@v2
+        uses: actions/setup-java@v4
         with:
           java-version: '21'
           distribution: 'temurin'