My maven clean install is suddenly started to fail when creating docker image. I am getting this 
Failed to execute goal com.spotify:dockerfile-maven-plugin:1.4.6:build (default) on project 01-hello-world-rest-api: Execution default of goal com.spotify:dockerfile-maven-plugin:1.4.6:build failed: null value in entry: https://index.docker.io/v1/=null → [Help 1]