Add sub-package info to environment-variables.mdx

docs/pages/repo/docs/handbook/environment-variables.mdx

@@ -31,3 +31,24 @@ We're actively looking forward to improving the developer experience and ergonom
 ## With global `turbo`
 
 If you're using `turbo` globally, you'll also need to install `dotenv-cli` globally so you can put `dotenv --` in front of the `turbo` command in your terminal.
+
+## With workspace scripts
+
+You may prefer to make your workspaces responsible for loading environment variables. This approach is more flexible, if you don't mind the extra configuration overhead in your `package.json` scripts.
+
+To use this strategy:
+
+1. Place all of your variables into the root of your monorepo as a `.env` file.
+
+2. Install `dotenv-cli` in the workspace.
+
+```json
+{
+  "scripts": {
++.   "dev": "dotenv -e ../../.env start-server"
+  }
+  "devDependencies": {
++    "dotenv-cli": "latest"
+  },
+}
+```