add lerna badge in README

[armujahid]

What I did

added lerna badge in README

How to test

• Is this testable with Jest or Chromatic screenshots? no need
• Does this need a new example in the kitchen sink apps? no need
• Does this need an update to the documentation? no need

[codecov]

Codecov Report

Merging #6064 into next will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             next    #6064   +/-   ##
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  Coverage   35.78%   35.78%           
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  Files         648      648           
  Lines        9520     9520           
  Branches     1352     1352           
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  Hits         3407     3407           
  Misses       5535     5535           
  Partials      578      578

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[shilman]

As much as I appreciate how Lerna helps us maintain Storybook (it's truly awesome!), I don't think this badge is informative at the top of our README. I'd be open to creating some kind of acknowledgments section elsewhere in the documentation if we can find a good place for it.

[armujahid]

@shilman something like this https://github.com/gatsbyjs/gatsby#a-note-on-how-this-repository-is-organized?

[shilman]

@armujahid Maybe add a sentence to the beginning of the Development scripts section?

Storybook is organized as a monorepo using [Lerna](https://lernajs.io). Useful scripts include:

[armujahid]

@shilman done

[shilman]

Thanks! 🙏