Dockerize the application

[eugenesimakin]

Make application available as docker image. This will make deployment an easy task.

Example of a guide: https://spring.io/guides/topicals/spring-boot-docker

Acceptance criteria:

• Dockerfile
• Docker image of the app should be publicly available at https://hub.docker.com/

[Washubrnfg85]

Dockerfile pushed to main. Link to image: https://hub.docker.com/r/archpj/link-sharing-app