OSB-45: specify context for dbinterface build

LCU/Maintenance/Docker/Jenkinsfile

@@ -20,7 +20,7 @@ pipeline {
                     }
                 
                     docker.build("lofar-maintenance-dbinterface:${DOCKER_TAG}",
-                                 "-f LCU/Maintenance/Docker/DBInterface/Dockerfile --build-arg TAG=${DOCKER_TAG}")
+                                 "-f LCU/Maintenance/Docker/DBInterface/Dockerfile --build-arg TAG=${DOCKER_TAG} .")
 
                     dir ('LCU/Maintenance/Docker/RESTService/'){
                         docker.build("lofar-maintenance-restservice:${DOCKER_TAG}", "--build-arg TAG=${DOCKER_TAG}")