Update README.md

Author: Code-Hex

README.md

@@ -1,5 +1,7 @@
 # go-generics-cache
 
+[![.github/workflows/test.yml](https://github.com/Code-Hex/go-generics-cache/actions/workflows/test.yml/badge.svg)](https://github.com/Code-Hex/go-generics-cache/actions/workflows/test.yml) [![codecov](https://codecov.io/gh/Code-Hex/go-generics-cache/branch/main/graph/badge.svg?token=Wm7UEwgiZu)](https://codecov.io/gh/Code-Hex/go-generics-cache)
+
 go-generics-cache is an in-memory key:value store/cache that is suitable for applications running on a single machine. This in-memory cache uses [Go Generics](https://go.dev/blog/generics-proposal) which will be introduced in 1.18.
 
 - implemented with [Go Generics](https://go.dev/blog/generics-proposal)
@@ -76,4 +78,4 @@ func main() {
 	decremented, _ := nc.Decrement("age", 1)
 	fmt.Println(decremented) // 26
 }
-```
+```