Bump postcss from 8.2.3 to 8.2.4 in /build/javascript (#617)

Bumps [postcss](https://github.com/postcss/postcss) from 8.2.3 to 8.2.4.
- [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/8.2.3...8.2.4)

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

build/javascript/package-lock.json

@@ -1776,9 +1776,9 @@
       }
     },
     "postcss": {
-      "version": "8.2.3",
-      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.2.3.tgz",
-      "integrity": "sha512-tdmNCCmxJEsLZNj810qlj8QbvnUNKFL9A5doV+uHrGGK/YNKWEslrytnHDWr9M/GgGjfUFwXCRbxd/b6IoRBXQ==",
+      "version": "8.2.4",
+      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.2.4.tgz",
+      "integrity": "sha512-kRFftRoExRVXZlwUuay9iC824qmXPcQQVzAjbCCgjpXnkdMCJYBu2gTwAaFBzv8ewND6O8xFb3aELmEkh9zTzg==",
       "dev": true,
       "requires": {
         "colorette": "^1.2.1",

build/javascript/package.json

@@ -16,7 +16,7 @@
   },
   "devDependencies": {
     "cssnano": "^4.1.10",
-    "postcss": "^8.2.3",
+    "postcss": "^8.2.4",
     "postcss-cli": "^8.3.1"
   },
   "snowpack": {