Integration tests on Spring Boot: webEnvironment required?

I created some integration tests, that tests methods of some repositories. I found that without:

@SpringBootTest(
    webEnvironment = SpringBootTest.WebEnvironment.MOCK,
    classes = ********.class
)

the tests don't run. I tried also with WebEnvironment.NONE, but I get

java.lang.IllegalStateException: Failed to load ApplicationContext

I don't understand why the web environment is required. Is there not a way to run an integration test on repositories without running the web environment?