PWA-1880: Add tailwind

[larsroettig]

Description

Adds tailwindcss and its dependencies to the appropriate package.json files within PWA Studio's monorepo

Related Issue

Closes PWA-1880

Acceptance

Acceptance Criteria

• Adds tailwindcss and its dependencies to the appropriate package.json files within PWA Studio's monorepo
• Updates our default Webpack configuration to include postcss-loader for CSS files
• Adds a postcss.config.js file to venia-concept and ensures it gets scaffolded
• Adds a tailwind.config.js file to venia-concept and ensures it gets scaffolded
• Includes the following properties in the Tailwind config file, based on the POC examples [app, theme]:
• mode
• presets
• purge
• separator

Verification Stakeholders

Specification

Verification Steps

Test scenario(s) for direct fix/feature

Test scenario(s) for any existing impacted features/areas

Test scenario(s) for any Magento Backend Supported Configurations

Is Browser/Device testing needed?

Any ad-hoc/edge case scenarios that need to be considered?

Screenshots / Screen Captures (if appropriate)

Breaking Changes (if any)

Checklist

• I have added tests to cover my changes, if necessary.
• I have added translations for new strings, if necessary.
• I have updated the documentation accordingly, if necessary.

[PWAStudioBot]

	Messages
📖	Associated JIRA tickets: PWA-1880.
📖	DangerCI Failures related to missing labels/description/linked issues/etc will persist until the next push or next nightly build run (assuming they are fixed).
📖	Access a deployed version of this PR here. Make sure to wait for the "pwa-pull-request-deploy" job to complete.

Generated by 🚫 dangerJS against 02f12c8

[revanth0212]

Please fix the lint errors mentioned in the danger comment.

[mikhaelbois]

✅ QA

• ✅ Build
• ✅ Scaffolding + Build
• ✅ Tests (Unit + Integration)
• ✅ Storybook