fix(scale_continuous): use bisect value iff gap in data

[nickofthyme]

Summary

#227

Revive fix for bad hover. #230

Before

After

Checklist

• This was checked for cross-browser compatibility, including a check against IE11
• Unit tests were updated or added to match the most common scenarios
• Each commit follows the convention

[codecov-io]

Codecov Report

Merging #328 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #328      +/-   ##
==========================================
+ Coverage   98.05%   98.05%   +<.01%     
==========================================
  Files          38       38              
  Lines        2726     2728       +2     
  Branches      643      644       +1     
==========================================
+ Hits         2673     2675       +2     
  Misses         48       48              
  Partials        5        5

Impacted Files	Coverage Δ
src/utils/scales/scale_continuous.ts	94.26% <100%> (+0.09%)	⬆️

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[nickofthyme]

Need to fix 👇

http://localhost:9001/?path=/story/grids--basic

[markov00]

close in favour of #346