Change CI to github actions from travis

README.md

@@ -2,7 +2,7 @@
 
 [![MIT License](https://img.shields.io/badge/license-MIT-blue.svg)](https://opensource.org/licenses/MIT)
 [![LoC](https://tokei.rs/b1/github/aergoio/heraj)](https://github.com/aergoio/heraj)
-[![Travis_ci](https://travis-ci.org/aergoio/heraj.svg?branch=develop)](https://travis-ci.org/aergoio/heraj)
+[![github build](https://github.com/aergoio/aergo/actions/workflows/gradle.yml/badge.svg)](https://github.com/aergoio/aergo/actions/workflows/gradle.yml/badge.svg)
 [![codecov.io](http://codecov.io/github/aergoio/heraj/coverage.svg?branch=develop)](http://codecov.io/github/aergoio/heraj?branch=develop)
 
 The hera is the client-side framework for the aergo.