Install @storybook/react-native in RN getstorybook

[shilman]

Issue: #1738

What I did

Fixes a bug introduced in #1652 where @storybook/react-native is no longer being installed by getstorybook for RN projects.

How to test

yarn bootstrap -- --core
cd ..
yarn create react-native-app crna
cd crna
../storybook/node_modules/\@storybook/cli/bin/generate.js
yarn storybook

Is this testable with jest or storyshots? No

Does this need a new example in the kitchen sink apps? No

Does this need an update to the documentation? No

If your answer is yes to any of these, please make sure to include it in your PR.

[codecov]

Codecov Report

Merging #1741 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1741   +/-   ##
=======================================
  Coverage   21.18%   21.18%           
=======================================
  Files         252      252           
  Lines        5694     5694           
  Branches      695      695           
=======================================
  Hits         1206     1206           
  Misses       3948     3948           
  Partials      540      540

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[tmeasday]

Looks reasonable although I have not ran the code

[ndelangen]

This is a no-brainer