First I created a container image repository in quay.io.
$ git clone https://github.com/spring-projects/spring-petclinic.git
$ spring-petclinic
$ sudo apt-get install openjdk-11-jdk -y
$ export JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64
$ ./mvnw spring-boot:build-image
$ docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
spring-petclinic 2.7.0-SNAPSHOT 73e160e426ea 42 years ago 266MB
$ docker tag spring-petclinic:2.7.0-SNAPSHOT quay.io/bmuthuka/spring-petclinic:2.7.0-SNAPSHOT
$ docker login quay.io # enter credentials when propmted
$ docker push quay.io/bmuthuka/spring-petclinic:2.7.0-SNAPSHOT