fix(docs): correct CI status badge URL (#87)

Author: calteran

README.md

@@ -1,6 +1,6 @@
 # oliframe
 
-[![oliframe](https://github.com/calteran/oliframe/actions/workflows/ci.yml/badge.svg?branch=main)](https://github.com/calteran/oliframe/actions/workflows/ci.yml)
+[![CI](https://github.com/calteran/oliframe/actions/workflows/ci.yml/badge.svg)](https://github.com/calteran/oliframe/actions/workflows/ci.yml)
 [![crates.io](https://img.shields.io/crates/v/oliframe.svg)](https://crates.io/crates/oliframe)
 [![codecov](https://codecov.io/github/calteran/oliframe/graph/badge.svg?token=8IWPNES6K2)](https://codecov.io/github/calteran/oliframe)
 [![MIT license](https://img.shields.io/badge/License-MIT-blue.svg)](https://calteran.mit-license.org/)