chore(deps): bump postcss from 8.4.21 to 8.4.31 in /frontend

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.21 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/8.4.21...8.4.31)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>

frontend/package-lock.json

@@ -4426,9 +4426,15 @@
       "dev": true
     },
     "node_modules/nanoid": {
-      "version": "3.3.4",
-      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.4.tgz",
-      "integrity": "sha512-MqBkQh/OHTS2egovRtLk45wEyNXwF+cokD+1YPf9u5VfJiRdAiRwB2froX5Co9Rh20xs4siNPm8naNotSD6RBw==",
+      "version": "3.3.6",
+      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.6.tgz",
+      "integrity": "sha512-BGcqMMJuToF7i1rt+2PWSNVnWIkGCU78jBG3RxO/bZlnZPK2Cmi2QaffxGO/2RvWi9sL+FAiRiXMgsyxQ1DIDA==",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/ai"
+        }
+      ],
       "bin": {
         "nanoid": "bin/nanoid.cjs"
       },
@@ -4816,9 +4822,9 @@
       }
     },
     "node_modules/postcss": {
-      "version": "8.4.21",
-      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.4.21.tgz",
-      "integrity": "sha512-tP7u/Sn/dVxK2NnruI4H9BG+x+Wxz6oeZ1cJ8P6G/PZY0IKk4k/63TDsQf2kQq3+qoJeLm2kIBUNlZe3zgb4Zg==",
+      "version": "8.4.31",
+      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.4.31.tgz",
+      "integrity": "sha512-PS08Iboia9mts/2ygV3eLpY5ghnUcfLV/EXTOW1E2qYxJKGGBUtNjN76FYHnMs36RmARn41bC0AZmn+rR0OVpQ==",
       "funding": [
         {
           "type": "opencollective",
@@ -4827,10 +4833,14 @@
         {
           "type": "tidelift",
           "url": "https://tidelift.com/funding/github/npm/postcss"
+        },
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/ai"
         }
       ],
       "dependencies": {
-        "nanoid": "^3.3.4",
+        "nanoid": "^3.3.6",
         "picocolors": "^1.0.0",
         "source-map-js": "^1.0.2"
       },
@@ -9608,9 +9618,9 @@
       "dev": true
     },
     "nanoid": {
-      "version": "3.3.4",
-      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.4.tgz",
-      "integrity": "sha512-MqBkQh/OHTS2egovRtLk45wEyNXwF+cokD+1YPf9u5VfJiRdAiRwB2froX5Co9Rh20xs4siNPm8naNotSD6RBw=="
+      "version": "3.3.6",
+      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.6.tgz",
+      "integrity": "sha512-BGcqMMJuToF7i1rt+2PWSNVnWIkGCU78jBG3RxO/bZlnZPK2Cmi2QaffxGO/2RvWi9sL+FAiRiXMgsyxQ1DIDA=="
     },
     "natural-compare": {
       "version": "1.4.0",
@@ -9871,11 +9881,11 @@
       }
     },
     "postcss": {
-      "version": "8.4.21",
-      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.4.21.tgz",
-      "integrity": "sha512-tP7u/Sn/dVxK2NnruI4H9BG+x+Wxz6oeZ1cJ8P6G/PZY0IKk4k/63TDsQf2kQq3+qoJeLm2kIBUNlZe3zgb4Zg==",
+      "version": "8.4.31",
+      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.4.31.tgz",
+      "integrity": "sha512-PS08Iboia9mts/2ygV3eLpY5ghnUcfLV/EXTOW1E2qYxJKGGBUtNjN76FYHnMs36RmARn41bC0AZmn+rR0OVpQ==",
       "requires": {
-        "nanoid": "^3.3.4",
+        "nanoid": "^3.3.6",
         "picocolors": "^1.0.0",
         "source-map-js": "^1.0.2"
       }