Insert 'yarn' command between 'cd storybook' and 'yarn bootstrap (--core)'
Insert 'yarn' command between 'cd storybook' and 'yarn bootstrap (--core)'

Signed-off-by: Yeseul Jeon <5637abf57736403a7ef388e2bf348732daa3bf6c@gmail.com>

storybooks/storybook,storybooks/storybook,storybooks/storybook,kadirahq/react-storybook,storybooks/storybook,storybooks/storybook,storybooks/react-storybook,storybooks/storybook,storybooks/storybook,kadirahq/react-storybook,storybooks/react-storybook,storybooks/react-storybook,storybooks/react-storybook