@Alpha
    default Collection<ExtensionHandlerCustomizer> getExtensionHandlerCustomizers(ConfigRegistry config) {
        return Collections.emptySet();
    }
Returns a collection of {@link ExtensionHandlerCustomizer} objects. These customizers are used
in addition to the customizers that have been registered with {@link Extensions#registerHandlerCustomizer}.
<br>
Handler customizers returned here can customize the behavior of the Handlers returned by the handler factories.

@param config A Configuration registry object that can be used to look up additional information
@return A collection of {@link ExtensionHandlerCustomizer} objects. Can be empty, must not be null

@since 3.38.0
core/src/main/java/org/jdbi/v3/core/extension/ExtensionFactory.java