fix(docs): update README to correct sync command for contract addresses and ABIs

Author: Ansonhkg

packages/contracts/README.md

@@ -12,7 +12,7 @@ All configs are in the `./src/config` directory
 # Syncing Contract Addresses and ABIs
 
 ```shell
-tsx ./src/index.ts
+tsx ./src/sync.ts
 ```
 
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