Symfony httplug bundle handle missing EventSubscriberInterface

In a Symfony 5.1.8 project I updated the httplug bundle to version 1.19.0.

It is mentioned in the changelog:

ConfiguredClientsStrategy no longer implements
EventSubscriberInterface, this has been moved to
ConfiguredClientsStrategyListener to avoid initializing the strategy
on every request.

That results in an error in In

EventDispatcher.php line 270

Failed to create closure from callable: class 'HttpHttplugBundleDiscoveryConfiguredClientsStrategy' does not have a method 'onEvent'

Any hint on how to resolve this issue is highly appreciated.

Source: Symfony Questions