feat: adds the option to show values for mixed time-series

[michael-s-molina]

🏆 Enhancements

Adds the option to show values for the mixed time-series chart.

@junlincc @rusackas

Screen.Recording.2021-10-26.at.10.56.25.AM.mov

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[codecov]

Codecov Report

Merging #1435 (60f1ae3) into master (a10ee4b) will not change coverage.
The diff coverage is 0.00%.

@@           Coverage Diff           @@
##           master    #1435   +/-   ##
=======================================
  Coverage   30.43%   30.43%           
=======================================
  Files         497      497           
  Lines       10000    10000           
  Branches     1689     1689           
=======================================
  Hits         3043     3043           
  Misses       6711     6711           
  Partials      246      246           

Impacted Files	Coverage Δ
...chart-echarts/src/MixedTimeseries/controlPanel.tsx	80.00% <ø> (ø)
...hart-echarts/src/MixedTimeseries/transformProps.ts	0.00% <0.00%> (ø)
.../plugin-chart-echarts/src/MixedTimeseries/types.ts	100.00% <ø> (ø)
...s/legacy-plugin-chart-country-map/src/countries.ts	0.00% <0.00%> (ø)

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[zhaoyongjie]

LGTM