Automigration for adding VTA on upgrade

[vanessayuenn]

When a user upgrades to Storybook 8, an automigration should run to add addon-visual-tests for them.

• It should explain the addon and what they will be opting into (text discussed below)
• It should only run if beforeVersion is < 8.0.x where x is the version we release this in

We want to ship this on Tuesday April 9.

[shilman]

Visual Tests addon

The Visual Tests addon lets you catch UI bugs faster and more easily than ever before. The addon brings Chromatic, the visual testing cloud service developed by Storybook maintainers, into Storybook for the very first time.

At the click of a button, you can test all your stories simultaneously, compare each one to previous versions, and pinpoint any visual changes. Then, filter your Storybook sidebar to only see stories containing visual differences and verify those changes one by one.

Learn more: https://storybook.js.org/blog/visual-tests-addon-beta/

Install Visual Tests addon into your project? [Y]/n

[joevaugh4n]

here’s a slightly shorter alternative. added ‘New to Storybook 8’ at the start, to make it feel more related to the upgrade - wdyt? @shilman @vanessayuenn

New to Storybook 8: Visual Tests addon is a new, official addon that performs automatic visual tests on Storybook stories. The addon is powered by Chromatic, a cloud-based visual testing tool developed by Storybook’s core team.

Learn more about Visual Tests addon: https://storybook.js.org/blog/visual-tests-addon-beta/

Install Visual Tests addon in your project? [Y]/n

[shilman]

@joevaugh4n I like the tone of this better, but it assumes that the reader knows what visual testing is. Can you please add a sentence to clarify? Thanks!