Output operation is missing a context parameter

There is no way to get context information when setting output data on a step setup.
This is especially required in the context of a loop like ForEach step.
For instance :
```C#
builder
.StartWith()
.ForEach(data => new List { 0, 1, 2, 3, 4 })
.Do(x => x
.StartWith()
.Output( (step, data, context) => data.Items[context.Item] = step.Return )
.Then())
.Then();
```