Update sample code snippet link in README.md

Author: Flouse

README.md

@@ -5,7 +5,7 @@ The target of this tutorial is very simple: use CKB SDKs in various languages to
 ## Sample Code
 Here's an example of how to write an on-chain message:
 
-https://github.com/Flouse/ckb-tthw/blob/42bf1b5a3566e2d8adf6ef79aad8580de0d79281/js/index.ts#L125-L136
+https://github.com/cryptape/ckb-tutorial/blob/42bf1b5a3566e2d8adf6ef79aad8580de0d79281/js/index.ts#L125-L136
 
 ## Tutorials in different languages
 - [JavaScript/TypeScript](./js/)