Simplify Configuring Operational Attributes in Embedded Test Servers

[jzheaux]

It would be nice if more of the underlying configuration settings were exposed for UnboundID's InMemoryDirectoryServerConfig. Specifically, it would be nice to add a custom operation interceptor so that test operational attributes can be added.

This would make testing for issues like #446 more flexible.

Instead of exposing support specifically for operational interceptors, though, it would be more flexible to expose a setter in unboundid.EmbeededLdapServerFactoryBean for post-processing the InMemoryDirectoryServerConfig like so:

public void setDirectoryServerConfigurationPostProcessor(Consumer<InMemoryDirectoryServerConfig> postProcessor)

Then, UnboundID's EmbeddedLdapServer could invoke that before starting the directory service, like so:

config.setEnforceAttributeSyntaxCompliance(true);
+ postProcessor.accept(config);

Entry entry ...

Tests should also be added to demonstrate that the constructed EmbeddedLdapServer correctly uses the configured post-processor.