Add polyfills to fix addon-actions in IE11

[Hypnosphi]

This is needed because react-inspector uses Symbol and Array#@@iterator

How to test

Open cra-kitchen-sink in IE11, navigate to Button/with text, press the button.

[codecov]

Codecov Report

Merging #1917 into master will decrease coverage by 0.01%.
The diff coverage is 0%.

@@            Coverage Diff            @@
##           master   #1917      +/-   ##
=========================================
- Coverage   21.31%   21.3%   -0.02%     
=========================================
  Files         257     257              
  Lines        5737    5741       +4     
  Branches      697     682      -15     
=========================================
  Hits         1223    1223              
- Misses       3975    4015      +40     
+ Partials      539     503      -36

Impacted Files	Coverage Δ
app/vue/src/server/config/polyfills.js	0% <0%> (ø)	⬆️
app/react/src/server/config/polyfills.js	0% <0%> (ø)	⬆️
...rc/modules/ui/components/left_panel/text_filter.js	30.98% <0%> (ø)	⬆️
lib/ui/src/modules/shortcuts/actions/shortcuts.js	6.25% <0%> (ø)	⬆️
lib/ui/src/modules/ui/configs/handle_routing.js	28.04% <0%> (ø)	⬆️
addons/knobs/src/KnobStore.js	6.81% <0%> (ø)	⬆️
...res__/update-addon-info/update-addon-info.input.js	0% <0%> (ø)	⬆️
addons/info/src/components/markdown/code.js	24.13% <0%> (ø)	⬆️
app/react/src/client/preview/error_display.js	0% <0%> (ø)	⬆️
lib/ui/src/modules/ui/routes.js	0% <0%> (ø)	⬆️
... and 24 more

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