Make the filter dropdown choices in the Filter Box cascading

[emlittleworth]

When a user selects a filter in the Filter Box visualization, the following filter dropdowns will be filtered based on that selection. It does not currently take the Filter Box time filter into consideration. I had to pull the FilterBox component into it's own file in order to export it for testing.

Before:

After:

Related issues: #5269, #5043, #4421, #3015, #5534

[codecov-io]

Codecov Report

Merging #5664 into master will increase coverage by 0.52%.
The diff coverage is 69.16%.

@@            Coverage Diff             @@
##           master    #5664      +/-   ##
==========================================
+ Coverage   63.49%   64.02%   +0.52%     
==========================================
  Files         360      361       +1     
  Lines       22889    22940      +51     
  Branches     2549     2557       +8     
==========================================
+ Hits        14534    14687     +153     
+ Misses       8340     8238     -102     
  Partials       15       15

Impacted Files	Coverage Δ
...ssets/src/visualizations/filter_box/filter_box.jsx	0% <0%> (ø)
superset/connectors/druid/models.py	83.65% <100%> (+1.09%)	⬆️
superset/views/core.py	74.12% <100%> (+0.19%)	⬆️
superset/connectors/base/models.py	91.5% <100%> (ø)	⬆️
superset/config.py	92.64% <100%> (+0.05%)	⬆️
superset/connectors/sqla/models.py	78.94% <52.17%> (+0.28%)	⬆️
...assets/src/visualizations/filter_box/FilterBox.jsx	77.95% <97.67%> (ø)
... and 2 more

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[mistercrunch]

Sorry that this PR got ignored so far. It's great work but as you know there's ongoing work in redesigning filters as dashboard native components and if we want to deprecate filter box, we may want (but not necessarily have to) to keep it as simple as possible.

@xtinec (working on filters)

[emlittleworth]

Yeah I definitely understand we probably don't want to introduce new functionality at the moment. I'll close this for now. @xtinec let me know if you want to chat about how it works if you decide to integrate cascading filter options!

[xtinec]

@emlittleworth love to chat about cascading filter options and incorporate it into the new design!

[srggrs]

@emlittleworth I'm interested to chat about it as well. How can we get in touch?

[ajones620]

@emlittleworth i'm also interested as well! are there any updates or is there any feedback i can contribute?

[jnthnvctr]

@xtinec and @emlittleworth - is this something that's still in progress?

[smic-datalabs-von]

Chiming in: Would definitely love this feature to be put up in Superset.

[t0nydean]

@emlittleworth or @xtinec or @mistercrunch Did this feature or something similar ever get finished?