build(deps-dev): bump postcss in /experimental/live-editor (#751)

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.6 to 8.4.12.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.4.6...8.4.12)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

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

experimental/live-editor/package.json

@@ -21,7 +21,7 @@
     "monaco-yaml": "file:./src/monaco-yaml",
     "pako": "^2.0.4",
     "path-browserify": "^1.0.0",
-    "postcss": "^8.4.5",
+    "postcss": "^8.4.12",
     "postcss-load-config": "^3.1.1",
     "prettier": "2.0.5",
     "svelte": "^3.44.0",

experimental/live-editor/yarn.lock

@@ -1304,10 +1304,10 @@ ms@2.1.2:
   resolved "https://registry.yarnpkg.com/ms/-/ms-2.1.2.tgz#d09d1f357b443f493382a8eb3ccd183872ae6009"
   integrity sha512-sGkPx+VjMtmA6MX27oA4FBFELFCZZ4S4XqeGOXCv68tT+jb3vk/RyaKWP0PTKyWtmLSM0b+adUTEvbs1PEaH2w==
 
-nanoid@^3.2.0:
-  version "3.2.0"
-  resolved "https://registry.yarnpkg.com/nanoid/-/nanoid-3.2.0.tgz#62667522da6673971cca916a6d3eff3f415ff80c"
-  integrity sha512-fmsZYa9lpn69Ad5eDn7FMcnnSR+8R34W9qJEijxYhTbfOWzr22n1QxCMzXLK+ODyW2973V3Fux959iQoUxzUIA==
+nanoid@^3.3.1:
+  version "3.3.2"
+  resolved "https://registry.yarnpkg.com/nanoid/-/nanoid-3.3.2.tgz#c89622fafb4381cd221421c69ec58547a1eec557"
+  integrity sha512-CuHBogktKwpm5g2sRgv83jEy2ijFzBwMoYA60orPDR7ynsLijJDqgsi4RDGj3OJpy3Ieb+LYwiRmIOGyytgITA==
 
 node-releases@^2.0.1:
   version "2.0.2"
@@ -1423,12 +1423,12 @@ postcss-value-parser@^4.2.0:
   resolved "https://registry.yarnpkg.com/postcss-value-parser/-/postcss-value-parser-4.2.0.tgz#723c09920836ba6d3e5af019f92bc0971c02e514"
   integrity sha512-1NNCs6uurfkVbeXG4S8JFT9t19m45ICnif8zWLd5oPSZ50QnwMfK+H3jv408d4jw/7Bttv5axS5IiHoLaVNHeQ==
 
-postcss@^8.4.5, postcss@^8.4.6:
-  version "8.4.6"
-  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.4.6.tgz#c5ff3c3c457a23864f32cb45ac9b741498a09ae1"
-  integrity sha512-OovjwIzs9Te46vlEx7+uXB0PLijpwjXGKXjVGGPIGubGpq7uh5Xgf6D6FiJ/SzJMBosHDp6a2hiXOS97iBXcaA==
+postcss@^8.4.12, postcss@^8.4.5, postcss@^8.4.6:
+  version "8.4.12"
+  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.4.12.tgz#1e7de78733b28970fa4743f7da6f3763648b1905"
+  integrity sha512-lg6eITwYe9v6Hr5CncVbK70SoioNQIq81nsaG86ev5hAidQvmOeETBqs7jm43K2F5/Ley3ytDtriImV6TpNiSg==
   dependencies:
-    nanoid "^3.2.0"
+    nanoid "^3.3.1"
     picocolors "^1.0.0"
     source-map-js "^1.0.2"