feat(legacy-plugin-chart-event-flow): migrate package

[kristw]

🏆 Enhancements

Move legacy-plugin-chart-event-flow from sandbox so it will get published with the control panel.

cc @suddjian

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[codecov]

Codecov Report

Merging #514 into master will decrease coverage by 0.11%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #514      +/-   ##
==========================================
- Coverage   22.63%   22.52%   -0.12%     
==========================================
  Files         281      285       +4     
  Lines        6692     6725      +33     
  Branches      648      651       +3     
==========================================
  Hits         1515     1515              
- Misses       5138     5171      +33     
  Partials       39       39              

Impacted Files	Coverage Δ
...s/legacy-plugin-chart-event-flow/src/EventFlow.jsx	0.00% <ø> (ø)
...egacy-plugin-chart-event-flow/src/controlPanel.jsx	0.00% <ø> (ø)
...lugins/legacy-plugin-chart-event-flow/src/index.js	0.00% <ø> (ø)
...gacy-plugin-chart-event-flow/src/transformProps.js	0.00% <ø> (ø)

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[rusackas]

LGTM