fix(docs): update CI badge link

Author: luisschwab

README.md

@@ -5,7 +5,7 @@ Bitcoin Esplora API client library. Supports plaintext, TLS and Onion servers. B
 <p>
     <a href="https://crates.io/crates/esplora-client"><img alt="Crate Info" src="https://img.shields.io/crates/v/esplora-client.svg"/></a>
     <a href="https://github.com/bitcoindevkit/rust-esplora-client/blob/master/LICENSE"><img alt="MIT Licensed" src="https://img.shields.io/badge/license-MIT-blue.svg"/></a>
-    <a href="https://github.com/bitcoindevkit/rust-esplora-client/actions/workflows/cont_integration.yml"><img alt="CI Status" src="https://github.com/bitcoindevkit/rust-esplora-client/workflows/Rust/badge.svg"></a>
+    <a href="https://github.com/bitcoindevkit/rust-esplora-client/actions/workflows/cont_integration.yml"><img alt="CI Status" src="https://github.com/bitcoindevkit/rust-esplora-client/actions/workflows/cont_integration.yml/badge.svg?branch=release/0.12.x"></a>
     <a href='https://coveralls.io/github/bitcoindevkit/rust-esplora-client?branch=master'><img src='https://coveralls.io/repos/github/bitcoindevkit/rust-esplora-client/badge.svg?branch=master' alt='Coverage Status' /></a>
     <a href="https://docs.rs/esplora-client"><img alt="API Docs" src="https://img.shields.io/badge/docs.rs-esplora--client-green"/></a>
     <a href="https://blog.rust-lang.org/2022/08/11/Rust-1.63.0.html"><img alt="Rustc Version 1.63.0+" src="https://img.shields.io/badge/rustc-1.63.0%2B-lightgrey.svg"/></a>