fix(deps): update dependency postcss-preset-env to v7 (#1194)

Co-authored-by: Renovate Bot <bot@renovateapp.com>
Co-authored-by: Clément Vannicatte <20689156+shortcuts@users.noreply.github.com>

Author: 3 people

packages/website/package.json

@@ -27,7 +27,7 @@
     "my-loaders": "file:plugins/my-loaders",
     "postcss": "8.3.11",
     "postcss-import": "14.0.2",
-    "postcss-preset-env": "6.7.0",
+    "postcss-preset-env": "7.0.1",
     "prism-react-renderer": "1.2.1",
     "react": "17.0.2",
     "react-dom": "17.0.2",