Forgot to add the link

                                /* Wait until mysql service is up */

                                sh 'while ! mysqladmin ping -hdb --silent; do sleep 1; done'

                            }

                            docker.image('maven:3-alpine').inside() {

                            docker.image('maven:3-alpine').inside("--link ${c.id}:db") {

                                    checkout scm

                                    sh 'mv src/main/resources/application.properties.production src/main/resources/application.properties'

                                    sh 'mvn test'

                                    sh 'mvn verify sonar:sonar'

                            }