fix(plugin-chart-table): check if control values are set

[villebro]

🐛 Bug Fix
When checking for visibility of server side related controls, make sure the control value is set before reading the control value.

[vercel]

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[codecov]

Codecov Report

Merging #1095 (34df7d4) into master (f9dec07) will not change coverage.
The diff coverage is 0.00%.

@@           Coverage Diff           @@
##           master    #1095   +/-   ##
=======================================
  Coverage   28.35%   28.35%           
=======================================
  Files         448      448           
  Lines        9057     9057           
  Branches     1423     1423           
=======================================
  Hits         2568     2568           
  Misses       6289     6289           
  Partials      200      200           

Impacted Files	Coverage Δ
plugins/plugin-chart-table/src/controlPanel.tsx	0.00% <0.00%> (ø)

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[zhaoyongjie]

LGTM