Include Scaling step in RRO Workflow Diagram

[MattKing06]

This is a sub-issue of #16455

To test:

• Build ReflectometryReductionOne-v1 documentation
• Check the workflow diagram is now complete and Scaling step is included

Fixes #16660

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[raquelalvarezbanos]

@MattKing06 I think we should mention this in the release notes, as it was pointed out by scientists.

[raquelalvarezbanos]

The Scaling step is displayed correctly. But now that I look at the diagram, I think the section between OutputWorkspace and Scale is not correct. From the diagram it seems that only when MomentumTransferMin AND MomentumTransferMax AND MomentumTransferStep are given, we apply the Rebin step. But looking at the code, if the first two are not given we try to calculate them from the IvsLam workspace, and if the last one, MomentumTransferStep, is not provided, we apply CalculateResolution (see here). So the three are dealt with independently and we always apply the Rebin step. Could we update this section as part of this PR?

[MattKing06]

@raquelalvarezbanos I agree, I'll see if I can fix this as part of this PR.

[raquelalvarezbanos]

Thanks @MattKing06 I think the important thing is to clarify how these are calculated: MomentumTransferMin and MomentumTransferMax from the equation Q = 4 \pi / \lambda * sin (\theta) and MomentumTransferStep from CalculateResolution. It is also important to clarify that the Rebin in Q is always applied.

[raquelalvarezbanos]

The workflow diagram is increasing in size but I think that is necessary if we want to document exactly what the algorithm does. Last section of the diagram (Rebin and Scale steps) looks more clear now in my opinion, it now documents how we calculate the necessary parameters for Rebin when those are not given by the user.