Fix broken colorpicker for knobs

[EloB]

Right now this error triggers when trying to open colorpicker but with this fix it least works but we get a warning.

Current issue

Uncaught TypeError: Cannot read property 'contains' of undefined
    at HTMLDocument.<anonymous> (velocity.js:13)

After this fix issue

Warning: Can't call setState (or forceUpdate) on an unmounted component. This is a no-op, but it indicates a memory leak in your application. To fix, cancel all subscriptions and asynchronous tasks in the componentWillUnmount method.
    in ColorPicker (created by ColorType)
    in div (created by Context.Consumer)
    in Styled(div) (created by ForwardRef)

[storybook-safe-bot]

	Fails
🚫	PR is not labeled with one of: ["cleanup","BREAKING CHANGE","feature request","bug","documentation","maintenance","dependencies:update","dependencies","other"]

Generated by 🚫 dangerJS

[codecov]

Codecov Report

Merging #4222 into master will decrease coverage by <.01%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master    #4222      +/-   ##
==========================================
- Coverage   40.79%   40.78%   -0.01%     
==========================================
  Files         493      493              
  Lines        5851     5852       +1     
  Branches      782      783       +1     
==========================================
  Hits         2387     2387              
  Misses       3088     3088              
- Partials      376      377       +1

Impacted Files	Coverage Δ
addons/knobs/src/components/types/Color.js	24% <0%> (-1%)	⬇️

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[Keraito]

Looks good to me, at least it works now. Any idea if we could get rid of the new warning as well?

[EloB]

@Keraito I didn't find that issue... It might be inside that colorpicker library... :(

[EloB]

@Keraito I found the issue inside the react-color library.

casesandberg/react-color#542

[EloB]

Can we release this one? I'm using this for theming and is totally broken right now.