It should be possible to provide custom Scheduler and Worker classes to ECSCluster

The ECS clusters have built-in scheduler and worker classes which are hard-coded into their configurations for firing up new tasks. It should be possible for users to subclass Scheduler and Worker and tell ECSCluster to use those subclasses instead. e.g. if we want to alter their behaviour at all in ways not exposed by ECSCluster itself.

Start by tracing ECSCluster's configuration for its built-in Scheduler and Worker classes. Confirm how existing cluster startup uses those classes, then verify that user-supplied subclasses are accepted and used when creating tasks.

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