chore(core): update README.md (#1302)

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Closes #issue_number

README.md

@@ -5,7 +5,7 @@ Ethereum Rust Execution L1 and L2 client.
 [![Telegram Chat][tg-badge]][tg-url]
 [![license](https://img.shields.io/github/license/lambdaclass/ethrex)](/LICENSE)
 
-[tg-badge]: https://img.shields.io/endpoint?url=https%3A%2F%2Ftg.sumanjay.workers.dev%2Frust_ethereum%2F&logo=telegram&label=chat&color=neon
+[tg-badge]: https://img.shields.io/endpoint?url=https%3A%2F%2Ftg.sumanjay.workers.dev%2Fethrex_client%2F&logo=telegram&label=chat&color=neon
 [tg-url]: https://t.me/ethrex_client
 
 # L1 and L2 support