Document limitations of using deferred JPA bootstrap

Closes gh-24027

Author: snicoll

spring-boot-project/spring-boot-docs/src/docs/asciidoc/spring-boot-features.adoc

@@ -3893,7 +3893,13 @@ To enable deferred or lazy bootstrapping, set the configprop:spring.data.jpa.rep
 When using deferred or lazy bootstrapping, the auto-configured `EntityManagerFactoryBuilder` will use the context's `AsyncTaskExecutor`, if any, as the bootstrap executor.
 If more than one exists, the one named `applicationTaskExecutor` will be used.
 
-NOTE: When using deferred or lazy bootstraping, make sure to defer any access to the JPA infrastructure after the application context bootstrap phase.
+[NOTE]
+====
+When using deferred or lazy bootstraping, make sure to defer any access to the JPA infrastructure after the application context bootstrap phase.
+You can use `SmartInitializingSingleton` to invoke any initialization that requires the JPA infrastructure.
+For JPA components (such as converters) that are created as Spring beans, use `ObjectProvider` to delay the resolution of dependencies, if any.
+====
+
 
 TIP: We have barely scratched the surface of Spring Data JPA.
 For complete details, see the {spring-data-jdbc-docs}[Spring Data JPA reference documentation].