How to prevent spring boot from auto creating instance of bean 'entityManagerFactory' at startup?

I am working on a Spring boot application that uses Spring JPA with PostgreSQL. I am using @SpringBootTest(classes = <my package>.Application.class) to initialize my unit test for a controller class. The problem is that this is causing the entityManagerFactory bean (and many other objects related to jpa, datasource, jdbc, etc.) to be created which is not needed for unit tests. Is there a way to prevent Spring from automatically creating these objects till they are actually used the first time? I spent a lot of time trying to load up only the beans I need for my unit test but ran into many errors. I am relatively new to Spring and I am hoping someone else has run into this before...and can help. I can post code snippets if needed.