Merge pull request #213 from spatial-model-editor/dependabot/npm_and_yarn/postcss-8.4.21

Bump postcss from 8.4.20 to 8.4.21

Author: lkeegan

package-lock.json

@@ -31,7 +31,7 @@
     "css-minimizer-webpack-plugin": "4.2.2",
     "html-minifier": "4.0.0",
     "mini-css-extract-plugin": "2.7.2",
-    "postcss": "8.4.20",
+    "postcss": "8.4.21",
     "postcss-loader": "7.0.1",
     "pug": "3.0.2",
     "sass": "1.57.1",