Storybook PostCSS Deprecation Warning

[chawes13]

When running the storybook build, we receive the following deprecation warning:

info => Using implicit CSS loaders
(node:87882) DeprecationWarning: Default PostCSS plugins are deprecated. When switching to '@storybook/addon-postcss',
you will need to add your own plugins, such as 'postcss-flexbugs-fixes' and 'autoprefixer'.

See https://github.com/storybookjs/storybook/blob/next/MIGRATION.md#deprecated-default-postcss-plugins for details.
(Use `node --trace-deprecation ...` to show where the warning was created)

Environment

• @launchpad/lp-components version: 7.0.0
• react version: 17.x
• node version: 16.14.0

Expected Behavior

Ideally we wouldn't see this warning message.

Current Behavior

At the moment, it does appear that functionally Storybook is working as expected. Still, we should resolve the issue that is causing this warning to ensure that nothing now (or in the future) is broken.

Steps to Reproduce

Run yarn storybook:build.

Suggested Solution

Follow the instructions here: https://github.com/storybookjs/storybook/blob/next/MIGRATION.md#deprecated-default-postcss-plugins

[chawes13]

Credit: @mwislek raised this in #573