title: Spring ConditionalOnProperty cannot read property in custom.properties file
body: <p>Hi I have some custom properties files like application.properties.And I put some property in this files.Myproblem is @ConditionalOnProperty cannot read myproperties in customproperties file.
  If I put same property in application.properties ConditionalOnProperty works but when I put myproperty in customproperties file that time it is not working.Except ConditionalOnProperty I dont have any problem to read values from custom properties file.Is there any way to read external properties from ConditionalOnProperty in spring boot.</p>
  
  <pre><code>@Congiuration
  @PropertySource("classpath:myproperties.properties")
  @ConfigurationProperties(prefix="mycustomprop")
  public class MyProperties{
  private String myproperty;
  
  
  @Configuration
  @ConditionalOnProperty(name = "mycustomprop.myproperty", havingValue = "false") //not work when myproperty in customproperty file
  public class MyConfiguration implements WebMvcConfigurer
  
  
  
  @SpringBootApplication
  @PropertySources({
          @PropertySource("classpath:myproperties.properties")
  })
  
  public class MyApplication
  </code></pre>