Update PostCSS dependencies (#23835)

package.json

@@ -37,7 +37,7 @@
     "abortcontroller-polyfill": "^1.7.5",
     "array-includes": "^3.1.6",
     "arrow-key-navigation": "^1.2.0",
-    "autoprefixer": "^9.8.8",
+    "autoprefixer": "^10.4.13",
     "axios": "^1.3.4",
     "babel-loader": "^8.3.0",
     "babel-plugin-lodash": "^3.3.4",
@@ -51,7 +51,7 @@
     "compression-webpack-plugin": "^6.1.1",
     "cross-env": "^7.0.3",
     "css-loader": "^5.2.7",
-    "cssnano": "^4.1.11",
+    "cssnano": "^5.1.15",
     "detect-passive-events": "^2.0.3",
     "dotenv": "^16.0.3",
     "emoji-mart": "npm:emoji-mart-lazyload@latest",
@@ -85,7 +85,7 @@
     "pg": "^8.5.0",
     "pg-connection-string": "^2.5.0",
     "postcss": "^8.4.21",
-    "postcss-loader": "^3.0.0",
+    "postcss-loader": "^4.3.0",
     "promise.prototype.finally": "^3.1.4",
     "prop-types": "^15.8.1",
     "punycode": "^2.3.0",

postcss.config.js

@@ -1,6 +1,6 @@
 module.exports = ({ env }) => ({
-  plugins: {
-    autoprefixer: {},
-    cssnano: env === 'production' ? {} : false,
-  },
+  plugins: [
+    'autoprefixer',
+    env === 'production' ? 'cssnano' : '',
+  ],
 });