fix(Dropdown): closing the search menu on spacebar press

[honzajerabek]

Fixes the #3764 .

In tests, I've only focused on open/closed state of the Dropdown components, because DropdownItem gets automatically set active and selected, which is probably a different issue (#3130 ), so I decided not to dig into it.

[welcome]

💖 Thanks for opening this pull request! 💖

Here is a list of things that will help get it across the finish line:

• Run yarn lint locally to catch formatting errors. This will fix some errors automatically, commit and push any changes.
• Run yarn test locally to catch errors. This ensures all components still behave as they should.
• Run yarn start to run the doc site locally and try a few pages, ensuring everything is in good working order.
• Include tests when adding/changing behavior.

We get a lot of pull requests on this repo, so please be patient and we will get back to you as soon as we can.

[codecov-io]

Codecov Report

Merging #3766 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #3766   +/-   ##
=======================================
  Coverage   99.84%   99.84%           
=======================================
  Files         175      175           
  Lines        3125     3125           
=======================================
  Hits         3120     3120           
  Misses          5        5

Impacted Files	Coverage Δ
src/modules/Dropdown/Dropdown.js	100% <ø> (ø)	⬆️
src/modules/Popup/Popup.js	98.71% <0%> (ø)	⬆️

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[evanstern]

👍 Thanks for getting this done so fast!

[ambroselittle]

Seems like the right quick fix for this.

[layershifter]

Tested in manually, works like a charm 💎

Thank you for fixing this ❤️

[welcome]

Congrats on merging your first pull request! 🎉🎉🎉