Bump postcss and parcel in /demo

[dependabot]

Removes postcss. It's no longer used after updating ancestor dependency parcel. These dependencies need to be updated together.

Removes postcss

Updates parcel from 1.12.3 to 2.9.3

Release notes

Sourced from parcel's releases.

v2.9.3

Fixed

• Resolver

  • Fix the development and production package conditions – Details

• JavaScript

  • Update SWC to fix generics in JSX elements – Details

v2.9.2

Fixed

• Core
  • Fix infinite loop when entries look like globs – Details
  • Fix proxyrc require from path – Details
• JavaScript
  • Treat re-exports of * from empty files with sideEffects: false as ESM – Details
• CSS
  • Fix self references error in CSS module JS assets causing "Bundle group cannot have more than one entry bundle of the same type" – Details
• Dev server
  • Serve folder's index when requesting folder without slash – Details
• Web extensions
  • Allow source maps files in webextension – Details
• Image
  • Add core as peerdep to image optimizer – Details

v2.9.1

Fixed

• Resolver
  • Ignore invalid package.json "type" field values – Details
  • Ignore duplicate slashes at the start of relative path specifiers – Details

v2.9.0

Parcel v2.9.0 includes many long requested features, including a brand new resolver with support for package.json "exports" and tsconfig.json features, support for ESM plugins and configs, and local Parcel plugins. It also improves performance with a new default JS minifier powered by SWC, incremental symbol propagation, and improved bundler data structures.

Blog post: https://parceljs.org/blog/v2-9-0/

Added

• Core

  • Add support for ESM plugins and configs – Details
  • Add support for local parcel plugins – Details
  • Incremental Symbol Propagation for improved performance and improved export errors in development – Details
  • Add support for plugin tracing, which shows where time is being spent during a Parcel build – Details
  • Support .proxyrc.cjs config files – Details
  • Add support for loadConfig function to resolver plugins – Details

• Resolver

  • New resolver implementation in Rust supporting package.json "exports" and "imports", and tsconfig.json "baseUrl", "paths", and "moduleSuffixes" – Details

... (truncated)

Changelog

Sourced from parcel's changelog.

[2.9.3] – 2023-06-24

Fixed

• Resolver

  • Fix the development and production package conditions – Details

• JavaScript

  • Update SWC to fix generics in JSX elements – Details

[2.9.2] - 2023-06-08

Fixed

• Core

  • Fix infinite loop when entries look like globs – Details
  • Fix proxyrc require from path – Details

• JavaScript

  • Treat re-exports of * from empty files with sideEffects: false as ESM – Details

• CSS

  • Fix self references error in CSS module JS assets causing "Bundle group cannot have more than one entry bundle of the same type" – Details

• Dev server

  • Serve folder's index when requesting folder without slash – Details

• Web extensions

  • Allow source maps files in webextension – Details

• Image

  • Add core as peerdep to image optimizer – Details

[2.9.1] - 2023-06-07

Fixed

• Resolver
  • Ignore invalid package.json "type" field values – Details
  • Ignore duplicate slashes at the start of relative path specifiers – Details

[2.9.0] - 2023-05-26

Added

• Core
  • Add support for ESM plugins and configs – Details
  • Add support for local parcel plugins – Details
  • Incremental Symbol Propagation for improved performance and improved export errors in development – Details
  • Add support for plugin tracing, which shows where time is being spent during a Parcel build – Details

... (truncated)

Commits

• db3bcae v2.9.3
• 34103e2 Updated SWC crate for JS Transformer (#9104)
• b79eab8 Bump semver from 5.7.1 to 7.5.2 (#9107)
• 76e7100 Fix the development and production package conditions (#9108)
• 76aa20f Changelog for v2.9.2
• 6e346c8 v2.9.2
• 40bf1c2 Fix self references in CSS module JS assets (#9080)
• f7fedaf Serve folder's index when requesting folder without slash (#9066)
• 4db35cd Treat re-exports of '*' from empty files as ESM (#9079)
• 44c5d73 Add core as peerdep to image optimizer (#9070)
• Additional commits viewable in compare view

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