Bump postcss from 8.4.30 to 8.4.31 (#1625)

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.30 to 8.4.31.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.4.30...8.4.31)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: direct:production
...

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

package.json

@@ -52,7 +52,7 @@
     "passport-http-bearer": "^1.0.1",
     "passport-jwt": "^4.0.1",
     "passport-local": "^1.0.0",
-    "postcss": "^8.4.30",
+    "postcss": "^8.4.31",
     "rc": "1.2.8",
     "redux": "4.2.1",
     "request-promise": "^4.2.6",