Update README badges to GitHub Actions CI and coverage

Author: Fivell

README.md

@@ -1,8 +1,8 @@
 [![Gem Version](https://badge.fury.io/rb/active_admin_datetimepicker.svg)](http://badge.fury.io/rb/active_admin_datetimepicker)
 [![NPM Version](https://badge.fury.io/js/@activeadmin-plugins%2Factive_admin_datetimepicker.svg)](https://badge.fury.io/js/@activeadmin-plugins%2Factive_admin_datetimepicker)
 ![npm](https://img.shields.io/npm/dm/@activeadmin-plugins/active_admin_datetimepicker)
-[![Build Status](https://img.shields.io/travis/activeadmin-plugins/active_admin_datetimepicker.svg)](https://travis-ci.org/activeadmin-plugins/active_admin_datetimepicker)
-[![Coverage](https://coveralls.io/repos/activeadmin-plugins/active_admin_datetimepicker/badge.svg?branch=master)](https://coveralls.io/r/activeadmin-plugins/active_admin_datetimepicker)
+[![CI](https://github.com/activeadmin-plugins/active_admin_datetimepicker/actions/workflows/ci.yml/badge.svg)](https://github.com/activeadmin-plugins/active_admin_datetimepicker/actions/workflows/ci.yml)
+![Coverage](https://img.shields.io/endpoint?url=https://activeadmin-plugins.github.io/active_admin_datetimepicker/badge.json)
 
 # ActiveAdminDatetimepicker