Update example

Author: febo

sdk/pubkey/README.md

@@ -25,7 +25,7 @@ pinocchio_pubkey::declare_id!("Ping111111111111111111111111111111111111111");
 
 Creating a `Pubkey` from a `&str`:
 ```rust
-let owner = pinocchio_pubkey::decode("7qtAvP4CJuSKauWHtHZJt9wmQRgvcFeUcU3xKrFzxKf1");
+let owner = pinocchio_pubkey::from_str("7qtAvP4CJuSKauWHtHZJt9wmQRgvcFeUcU3xKrFzxKf1");
 ```
 
 ## License