chore(deps): bump postcss from 8.5.10 to 8.5.23 in /explorer (#799)

Bumps [postcss](https://github.com/postcss/postcss) from 8.5.10 to 8.5.23.
- [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/8.5.10...8.5.23)

---
updated-dependencies:
- dependency-name: postcss
  dependency-version: 8.5.23
  dependency-type: indirect
...

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

explorer/package-lock.json

@@ -3099,9 +3099,9 @@
       "license": "MIT"
     },
     "node_modules/nanoid": {
-      "version": "3.3.11",
-      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.11.tgz",
-      "integrity": "sha512-N8SpfPUnUp1bK+PMYW8qSWdl9U+wwNWI4QKxOYDy9JAro3WMX7p2OeVRF9v+347pnakNevPmiHhNmZ2HbFA76w==",
+      "version": "3.3.16",
+      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.16.tgz",
+      "integrity": "sha512-bzlKTyNJ7+LdGIIwy8ijFpIqEQIvafahV7eYykJ8Cvh42EdJeODoJ6gUJXpQJvej1BddH8OqTXZNE/KfbWAu8Q==",
       "dev": true,
       "funding": [
         {
@@ -3290,9 +3290,9 @@
       }
     },
     "node_modules/postcss": {
-      "version": "8.5.10",
-      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.5.10.tgz",
-      "integrity": "sha512-pMMHxBOZKFU6HgAZ4eyGnwXF/EvPGGqUr0MnZ5+99485wwW41kW91A4LOGxSHhgugZmSChL5AlElNdwlNgcnLQ==",
+      "version": "8.5.23",
+      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.5.23.tgz",
+      "integrity": "sha512-g50586zr4bZmwFiTlflMu8E0bDTb5I5gertgwAKmsdUlTQIhZtunzUlD1WSzwcVWPoAVpsrA6vlfCD7oXvRwgg==",
       "dev": true,
       "funding": [
         {
@@ -3310,7 +3310,7 @@
       ],
       "license": "MIT",
       "dependencies": {
-        "nanoid": "^3.3.11",
+        "nanoid": "^3.3.16",
         "picocolors": "^1.1.1",
         "source-map-js": "^1.2.1"
       },