fix: set up Java for backend in .yml file

.github/workflows/main.yml

@@ -12,10 +12,10 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Set up Node.js for Frontend
-        uses: actions/setup-node@v2
+        uses: actions/setup-node@v4
         with:
           node-version: '20.17.0'
 
@@ -30,15 +30,15 @@ jobs:
           npm run build
 
       - name: Set up Java for Backend
-        uses: actions/setup-java@v2
+        uses: actions/setup-java@v4
         with:
-          distribution: 'oracle'
-          java-version: '22.0.2'
+          distribution: 'temurin'
+          java-version: '22'
 
       - name: Build Backend
         run: |
           cd backend
-          mvnw package
+          mvn -B package --file pom.xml
 
   deploy:
     runs-on: ubuntu-latest