[CI] Update sonar job to use cache@v4

Updates deprecated Node 16 to 20

Author: TobiGr

.github/workflows/ci.yml

@@ -123,7 +123,7 @@ jobs:
           cache: 'gradle'
 
       - name: Cache SonarCloud packages
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.sonar/cache
           key: ${{ runner.os }}-sonar