Add CI badges to README.md

Author: ryukinix

README.md

@@ -1,3 +1,6 @@
+![test](https://github.com/commonlispbr/troll-shield/workflows/test/badge.svg)
+![goreleaser](https://github.com/commonlispbr/troll-shield/workflows/goreleaser/badge.svg)
+[![codecov](https://codecov.io/gh/commonlispbr/troll-shield/branch/master/graph/badge.svg?token=8YZDC9BGZX)](https://codecov.io/gh/commonlispbr/troll-shield)
 # Usage
 
 ``` bash