Boot Actuator not triggering HttpHandler auto configuration when different port is used

[mtalbot]

When using spring web flux and Actuator where actuator is on a different port the HttpHandler autoconfiguration Annotation configuration bean class isn't triggered when the child management context is created. The outer configuration bean. This is different than the parent reactive application context.

To reproduce this all that is needed is a project with both org.springframework.boot:spring-boot-starter-actuator and org.springframework.boot:spring-boot-starter-webflux and

management:
  server:
    port: 8081

which will cause Caused by: org.springframework.context.ApplicationContextException: Unable to start ReactiveWebApplicationContext due to missing HttpHandler bean.