Add sidebarAnimations config prop

[michaltaberski]

Issue:

What I did

add option sidebarAnimations which allows to disable sidebar tree animation. By default animations are enabled

How to test

import { setOptions } from '@storybook/addon-options';

setOptions({
  sidebarAnimations: false,
});

[codecov]

Codecov Report

Merging #1601 into master will decrease coverage by 0.62%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master    #1601      +/-   ##
==========================================
- Coverage   21.05%   20.42%   -0.63%     
==========================================
  Files         244      241       -3     
  Lines        5311     5254      -57     
  Branches      669      666       -3     
==========================================
- Hits         1118     1073      -45     
+ Misses       3670     3654      -16     
- Partials      523      527       +4

Impacted Files	Coverage Δ
lib/ui/src/modules/api/index.js	0% <ø> (ø)	⬆️
...b/ui/src/modules/ui/components/left_panel/index.js	100% <ø> (ø)	⬆️
...les/ui/components/left_panel/stories_tree/index.js	100% <100%> (ø)	⬆️
lib/ui/src/modules/ui/containers/left_panel.js	25.71% <50%> (+0.71%)	⬆️
lib/ui/src/modules/ui/components/search_box.js	16.66% <0%> (-67.71%)	⬇️
lib/ui/src/modules/ui/containers/search_box.js	33.33% <0%> (-66.67%)	⬇️
lib/ui/src/compose.js	20% <0%> (-13.34%)	⬇️
...ponents/left_panel/stories_tree/tree_decorators.js	29.57% <0%> (-3.76%)	⬇️
lib/ui/src/modules/ui/containers/routed_link.js
... and 4 more

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[Hypnosphi]

LGTM

[Hypnosphi]

In fact, we can think about using CSS transitions instead of JS animation provided by react-treebeard to make things less laggy with heavy stories. But an ability to completely opt out of animations won't hurt anyway

[usulpro]

whether it will lead to the fact that in the future we will have a bunch of options for tweaking UI? I guess we'll able to provide the same options via UI components when it's ready

[ndelangen]

Indeed @usulpro