title: Error creating bean named `conversionServicePostProcessor` when using spring-boot-admin-server
body: <p>I was trying to enable Spring boot admin server for my application. The default settings work perfectly fine but when I attempt to enable security, I am getting following error:</p>
  
  <blockquote>
    <hr>
    
    <p>APPLICATION FAILED TO START</p>
    
    <hr>
    
    <p>Description:</p>
    
    <p>The bean 'conversionServicePostProcessor', defined in class path
    resource
    [org/springframework/security/config/annotation/web/configuration/WebSecurityConfiguration.class],
    could not be registered. A bean with that name has already been
    defined in class path resource
    [org/springframework/security/config/annotation/web/reactive/WebFluxSecurityConfiguration.class]
    and overriding is disabled.</p>
    
    <p>Action:</p>
    
    <p>Consider renaming one of the beans or enabling overriding by setting
    spring.main.allow-bean-definition-overriding=true</p>
    
    <p>Process finished with exit code 1</p>
  </blockquote>
  
  <p>I am using the latest SNAPSHOT version of <code>spring-boot-admin-starter-server</code> (2.2.0-SNAPSHOT). Here is my security configuration:</p>
  
  <pre><code>@EnableAdminServer
  @EnableWebFluxSecurity
  @Configuration(proxyBeanMethods = false)
  class AdminServerSecurityConfigurations(val adminServerProperties: AdminServerProperties) {
  
      @Bean
      fun adminServerSecurityWebFilterChain(http: ServerHttpSecurity): SecurityWebFilterChain = http
              // @formatter:off
              .authorizeExchange()
                  .pathMatchers("${adminServerProperties.contextPath}/assets/**").permitAll()
                  .pathMatchers("${adminServerProperties.contextPath}/login").permitAll()
                  .anyExchange().authenticated().and()
              .formLogin().loginPage("${adminServerProperties.contextPath}/login").and()
              .logout().logoutUrl("${adminServerProperties.contextPath}/logout").and()
              .httpBasic().and()
              // @formatter:on
              .csrf().disable()
              .build()
  
  
      @Bean
      fun notifyLogger(instanceRepository: InstanceRepository) = LoggingNotifier(instanceRepository)
  
  }
  </code></pre>