Merge remote-tracking branch 'origin/feature/8531_Refl_gui_selective_processing'
Fix saving a WorkspaceGroup in SANSBatchMode

It previously just saved the last thing in the group with the group name.
Now the group is unrolled and each workspace save individually.
Refs #8575
Merge branch 'feature/8575_save_workspace_groups_sans_batch' into develop