reverted maven.yml to use checkout@v4

upgraded to cache@v4

Author: lpandzic

.github/workflows/maven.yml

@@ -11,13 +11,13 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v2
       - name: Set up JDK 17
         uses: actions/setup-java@v1
         with:
           java-version: 17
       - name: Cache local Maven repository
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}