Incorrect minimal required node version

[hcz]

Issue: minimal required node in the package.json is not correct

What I did

I've installed dependencies

 storybook $ node -v
v8.9.4

 storybook $ yarn bootstrap
yarn run v1.19.0
$ node ./scripts/bootstrap.js
? Select the bootstrap activities Core, Dll & Examples (core)
storybook info bootstrap Install dependencies (install)
[1/5] 🔍  Validating package.json...
[2/5] 🔍  Resolving packages...
[3/5] 🚚  Fetching packages...
error @typescript-eslint/eslint-plugin@2.3.2: The engine "node" is incompatible with this module. Expected version "^8.10.0 || ^10.13.0 || >=11.10.1". Got "8.9.4"
error Found incompatible module.
info Visit https://yarnpkg.com/en/docs/cli/install for documentation about this command.
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

How to test

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

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

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