fix: remove series with undefined splitSeriesAccessor values

[markov00]

Summary

This PR removes every series generated from a partial datum where some or all the values accessed by the splitSeriesAccessors array are null or undefined.

fix #594

Checklist

Delete any items that are not applicable to this PR.

• Unit tests were updated or added to match the most common scenarios

[codecov-io]

Codecov Report

Merging #627 into master will increase coverage by 0.00%.
The diff coverage is 29.93%.

@@           Coverage Diff           @@
##           master     #627   +/-   ##
=======================================
  Coverage   67.78%   67.79%           
=======================================
  Files         236      236           
  Lines        6914     6916    +2     
  Branches     1275     1276    +1     
=======================================
+ Hits         4687     4689    +2     
  Misses       2208     2208           
  Partials       19       19           

Impacted Files	Coverage Δ
src/chart_types/index.ts	100.00% <ø> (ø)
src/mocks/specs/specs.ts	76.19% <ø> (ø)
...art_types/goal_chart/layout/viewmodel/viewmodel.ts	3.12% <3.12%> (ø)
...pes/goal_chart/renderer/canvas/canvas_renderers.ts	9.58% <9.58%> (ø)
...al_chart/state/selectors/on_element_over_caller.ts	18.42% <18.42%> (ø)
..._types/goal_chart/state/selectors/picked_shapes.ts	23.52% <23.52%> (ø)
...l_chart/state/selectors/on_element_click_caller.ts	29.62% <29.62%> (ø)
...oal_chart/state/selectors/on_element_out_caller.ts	31.81% <31.81%> (ø)
src/state/chart_state.ts	84.21% <33.33%> (ø)
...goal_chart/renderer/canvas/connected_component.tsx	34.42% <34.42%> (ø)
... and 14 more

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[nickofthyme]

Code changes look good. Tested storybook and looks good.

Would we ever want in the future to enable this functionality under other if a prop were passed, say includeMissingSplitGroups or something?