Bump postcss from 8.4.29 to 8.4.31 in /ui (#1059)

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.29 to 8.4.31.
- [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/8.4.29...8.4.31)

---
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>

ui/package-lock.json

@@ -18,7 +18,7 @@
         "cssnano": "^6.0.1",
         "mime": "^3.0.0",
         "pascal-case": "^3.1.2",
-        "postcss": "^8.4.29",
+        "postcss": "^8.4.31",
         "postcss-load-config": "^4.0.1",
         "rollup": "^3.28.1",
         "rollup-plugin-css-only": "^4.3.0",
@@ -2290,9 +2290,9 @@
       }
     },
     "node_modules/postcss": {
-      "version": "8.4.29",
-      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.4.29.tgz",
-      "integrity": "sha512-cbI+jaqIeu/VGqXEarWkRCCffhjgXc0qjBtXpqJhTBohMUjUQnbBr0xqX3vEKudc4iviTewcJo5ajcec5+wdJw==",
+      "version": "8.4.31",
+      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.4.31.tgz",
+      "integrity": "sha512-PS08Iboia9mts/2ygV3eLpY5ghnUcfLV/EXTOW1E2qYxJKGGBUtNjN76FYHnMs36RmARn41bC0AZmn+rR0OVpQ==",
       "dev": true,
       "funding": [
         {

ui/package.json

@@ -21,7 +21,7 @@
     "cssnano": "^6.0.1",
     "mime": "^3.0.0",
     "pascal-case": "^3.1.2",
-    "postcss": "^8.4.29",
+    "postcss": "^8.4.31",
     "postcss-load-config": "^4.0.1",
     "rollup": "^3.28.1",
     "rollup-plugin-css-only": "^4.3.0",