fix fmt readme

Author: MauroToscano

examples/l2/README.md

@@ -146,15 +146,15 @@ make gen_devnet_owner_wallet
 
 Finally, generate the program id with:
 
-````shell
+```shell
 make generate_program_id
 ```
 
 Copy the address to the generated `.env` and deploy the contract:
 
 ```shell
 make deploy_contract
-````
+```
 
 Pass the output address in the `.env` and [run the l2](#run-the-l2).