fix: update CI badge link (#300)

Shields made a breaking change so unbreak it.

Refs badges/shields#8671

Author: achingbrain

README.md

@@ -2,7 +2,7 @@
 
 [![multiformats.io](https://img.shields.io/badge/project-IPFS-blue.svg?style=flat-square)](http://multiformats.io)
 [![codecov](https://img.shields.io/codecov/c/github/multiformats/js-multiaddr.svg?style=flat-square)](https://codecov.io/gh/multiformats/js-multiaddr)
-[![CI](https://img.shields.io/github/workflow/status/multiformats/js-multiaddr/test%20&%20maybe%20release/master?style=flat-square)](https://github.com/multiformats/js-multiaddr/actions/workflows/js-test-and-release.yml)
+[![CI](https://img.shields.io/github/actions/workflow/status/multiformats/js-multiaddr/js-test-and-release.yml?branch=master\&style=flat-square)](https://github.com/multiformats/js-multiaddr/actions/workflows/js-test-and-release.yml?query=branch%3Amaster)
 
 > multiaddr implementation (binary + string representation of network addresses)