Testing Entire Process Path, servlet

I have a SpringBoot Camunda process application which runs in a shared tomcat environment.
I would like to run scenario tests which spin up an in-memory process engine to test the entire process path, and to do this I’ve been using

@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest(properties = {"camunda.bpm.process-engine-name=default"})
@ContextConfiguration(classes =MyCamundaSpringApplicationContext.class)
public class MyScenarioTest {

    @Autowired
    private ProcessEngine processEngine;

    @Rule
    @ClassRule
    public static ProcessEngineRule processEngineRule;
    public ProcessInstance processInstance;

    @PostConstruct
    void initRule() {
        processEngineRule = TestCoverageProcessEngineRuleBuilder
                .create(processEngine)
                .withDetailedCoverageLogging()
                .build();
    }

With my application class being defined as:

@SpringBootApplication
@EnableProcessApplication
public class MySpringBootApplication {

  public static void main(String[] args) {

    SpringApplication.run(MySpringBootApplication.class);

  }
}

This requires me to have Camunda spring starter as a provided dependency. I’d prefer to use my application as:

@SpringBootApplication
public class MySpringBootApplication extends SpringServletProcessApplication {
  public static void main(String[] args) {

    SpringApplication.run(MySpringBootApplication.class);

  }
}

but when I run my scenario tests the process engine is null.