CLI: Do not show a migration summary on sb init

[yannbf]

Closes #

What I did

This PR makes the sb init not display the migration summary, as it's quite confusing to see notes about migration when starting a fresh Storybook project.

Before:

After:

How to test

1. build the cli
2. run code/lib/cli/bin/index.js init on a project
3. notice that there's no summary anymore

Checklist

• Make sure your changes are tested (stories and/or unit, integration, or end-to-end tests)
• Make sure to add/update documentation regarding your changes
• If you are deprecating/removing a feature, make sure to update
  MIGRATION.MD

Maintainers

• If this PR should be tested against many or all sandboxes,
  make sure to add the ci:merged or ci:daily GH label to it.
• Make sure this PR contains one of the labels below.

["cleanup", "BREAKING CHANGE", "feature request", "bug", "documentation", "maintenance", "dependencies", "other"]

[shilman]

Would it be better to simply not run automigrations at all on init?

[yannbf]

Would it be better to simply not run automigrations at all on init?

We've asked ourselves this question a few times, the reason we run them is because Storybook does not support Typescript out of the box for a subset of projects (then we run the babelrc migration). I'd love if we didn't have to run them!

We also ask whether people would like to install the eslint plugin, but that one in particular could be done in a different way for sure