InitializeUserDetailsBeanManagerConfigurer should respect primary flag

Expected Behavior
If one of multiple UserDetailsService beans is primary, then it should be configured.

Current Behavior
Warning log message instead.

https://github.com/spring-projects/spring-security/blob/c905ac359dde44cb35bca688444438c2b8fe6beb/config/src/main/java/org/springframework/security/config/annotation/authentication/configuration/InitializeUserDetailsBeanManagerConfigurer.java#L86-L92

Context

I want to enhance existing UserDetailsService like this:

    @Primary
    @Bean
    public UserDetailsService primaryUserDetailsService(UserDetailsService userDetailsService) {
        return (username) -> {
            // TODO load user from other source
            return userDetailsService.loadUserByUsername(username);
        };
    }

I'd like to contribute if it's accepted.

Start by reading config/src/main/java/org/springframework/security/config/annotation/authentication/configuration/InitializeUserDetailsBeanManagerConfigurer.java around lines 86-92 and trace how multiple UserDetailsService beans are handled. Verify the primary bean case, then add coverage showing that a primary UserDetailsService is configured instead of producing the warning.