chore: add a note to the pivot plugin

[betodealmeida]

🏠 Internal

We reproduce the logic of the pivot table viz in Python to produce nice reports. I added a note that if the logic of the plugin changes we need to update the Python logic.

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[codecov]

Codecov Report

Merging #1316 (1889af6) into master (358733c) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1316   +/-   ##
=======================================
  Coverage   29.93%   29.93%           
=======================================
  Files         487      487           
  Lines        9837     9837           
  Branches     1647     1647           
=======================================
  Hits         2945     2945           
  Misses       6656     6656           
  Partials      236      236           

Impacted Files	Coverage Δ
...s/plugin-chart-pivot-table/src/PivotTableChart.tsx	0.00% <ø> (ø)

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