Fix incorrect yarn command in docs

[Hypnosphi]

No description provided.

[danielduan]

👍

[codecov]

Codecov Report

Merging #1758 into release/3.3 will not change coverage.
The diff coverage is n/a.

@@             Coverage Diff              @@
##           release/3.3    #1758   +/-   ##
============================================
  Coverage        23.12%   23.12%           
============================================
  Files              253      253           
  Lines             5756     5756           
  Branches           686      700   +14     
============================================
  Hits              1331     1331           
+ Misses            3943     3912   -31     
- Partials           482      513   +31

Impacted Files	Coverage Δ
addons/knobs/src/KnobManager.js	32% <0%> (ø)	⬆️
addons/knobs/src/components/PropForm.js	8.51% <0%> (ø)	⬆️
...res__/update-addon-info/update-addon-info.input.js	0% <0%> (ø)	⬆️
addons/knobs/src/components/types/Number.js	8.06% <0%> (ø)	⬆️
lib/codemod/src/transforms/update-addon-info.js	51.16% <0%> (ø)	⬆️
...ponents/left_panel/stories_tree/tree_decorators.js	33.33% <0%> (ø)	⬆️
...rc/modules/ui/components/left_panel/text_filter.js	30.98% <0%> (ø)	⬆️
app/react-native/src/bin/storybook-build.js	0% <0%> (ø)	⬆️
app/react-native/src/preview/story_kind.js	0% <0%> (ø)	⬆️
lib/ui/src/libs/key_events.js	23.25% <0%> (ø)	⬆️
... and 15 more

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