Bump postcss from 8.3.1 to 8.3.2 in /build/javascript (#1094)

Bumps [postcss](https://github.com/postcss/postcss) from 8.3.1 to 8.3.2.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](https://github.com/postcss/postcss/compare/8.3.1...8.3.2)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

build/javascript/package.json

@@ -15,7 +15,7 @@
   },
   "devDependencies": {
     "cssnano": "^5.0.5",
-    "postcss": "^8.3.1",
+    "postcss": "^8.3.2",
     "postcss-cli": "^8.3.1"
   },
   "snowpack": {