SpringBoot Use loop variable ApplicationContext to determine all Liquibase beans

https://github.com/spring-projects/spring-boot/blob/d2926e02222f942948637bd5bb6972379eb094c8/spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/liquibase/LiquibaseEndpoint.java#L65

should be replaced with target.getBeansOfType(SpringLiquibase.class)

Comment From: wilkinsona

Closing in favour of #22681.