chore(deps): update postcss-preset-env to v11

Exported as ESM (csstools/postcss-plugins#1763).

package.json

@@ -140,7 +140,7 @@
     "postcss": "^8.5.6",
     "postcss-import": "^16.1.1",
     "postcss-loader": "^8.2.0",
-    "postcss-preset-env": "^10.6.1",
+    "postcss-preset-env": "^11.1.2",
     "prettier": "~2.7.1",
     "pretty-quick": "^3.3.1",
     "primer-tooltips": "^2.0.0",

postcss.config.js

@@ -1,6 +1,7 @@
 module.exports = {
 	plugins: [
 		require("postcss-import")(),
+		// @ts-ignore FIXME: ts-node can't import this on CommonJS
 		require("postcss-preset-env")(),
 		require("cssnano")({
 			preset: [