Batch domain interface representing the configuration of a step. As with the Job, a Step is meant to
explicitly represent the configuration of a step by a developer, but also the ability to execute the step.
Process the step and assign progress and status meta information to the StepExecution provided. The
Step is responsible for setting the meta information and also saving it if required by the
It is not safe to re-use an instance of Step to process multiple concurrent executions.
stepExecution - an entity representing the step to be executed