docs: restore broken link (#1885)

* Update erc7984-tutorial.md

Restore broken link

* docs: update erc7984-tutorial.md

Author: sebastien-nerot

docs/examples/openzeppelin/erc7984-tutorial.md

@@ -20,7 +20,7 @@ Before starting this tutorial, ensure you have:
 2. Set up the OpenZeppelin confidential contracts library 
 
 For help with these steps, refer to the following tutorial:
-- [Setting up OpenZeppelin confidential contracts](./openzeppelin/README.md)
+- [Setting up OpenZeppelin confidential contracts](./README.md)
 
 ## Understanding the architecture