ChromeDevToolsServiceConfiguration creates unused ExecutorService

[selevt]

Creating an instance of the ChromeDevToolsServiceConfiguration also results in the creation of an ExecutorService (through the DefaultEventExecutorService). That executor is not used in case the service is cached (and not shut down).

Some possible solutions:

• Don't create a default DefaultEventExecutorService in the ChromeDevToolsServiceConfiguration, but only if required and no custom one is specified in the config.
• Have a Supplier as part of the config, which is only invoked if required.