'children' viewhint for data_sets in sensor panes

[#37549847]
'Children' viewhint for data_sets in prediction

[#37549831]
Testing adding in_legend to data_set join model
Trying changed view hints for join
Whitespace cleanup
Cards for SensorPane/DataSet relationship models

[#37445619]
Merge branch 'master' into graph-pane-data-legends

Getting the "children" viewhints for in_legend work