Update v2->v4 maven.yaml

Author: Elisedlund-ericsson

.github/workflows/maven.yaml

@@ -20,7 +20,7 @@ jobs:
                   java-version: ${{ matrix.java }}
                   architecture: x64
             - name: Cache Maven packages
-              uses: actions/cache@v2
+              uses: actions/cache@v4
               with:
                   path: ~/.m2
                   key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}