[Dotenv] Documentation improvement

Author: jonmldr

README.md

@@ -2,7 +2,7 @@ Dotenv Component
 ================
 
 Symfony Dotenv parses `.env` files to make environment variables stored in them
-accessible via `$_SERVER`, `$_ENV` and optionally `getenv()`.
+accessible via `$_SERVER` or `$_ENV`.
 
 Resources
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