Update .gitlab-ci.yml

.gitlab-ci.yml

@@ -16,7 +16,6 @@ before_script:
     - docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" $CI_REGISTRY
 
 build:
-  image: maven:3-jdk-8:latest
   stage: build
   script:
     - docker build --pull -t "$CI_REGISTRY_IMAGE" .
@@ -24,7 +23,6 @@ build:
     - docker push "$CI_REGISTRY_IMAGE/$CI_PROJECT_NAME:latest"
 
 sonar:
-    image: maven:3-jdk-8:latest
     stage: test
     script:
     - mvn --batch-mode verify sonar:sonar -Dsonar.exclusions="pom.xml" -Dsonar.host.url=$SONAR_URL -Dsonar.login=$SONAR_LOGIN