Update README.md

Add pkg.go.dev Badge

Author: devlights

README.md

@@ -6,6 +6,7 @@ This is my TUTORIAL project for golang
 [![Go Report Card](https://goreportcard.com/badge/github.com/devlights/try-golang)](https://goreportcard.com/report/github.com/devlights/try-golang)
 ![Go](https://github.com/devlights/try-golang/workflows/Go/badge.svg?branch=master)
 [![Gitpod Ready-to-Code](https://img.shields.io/badge/Gitpod-Ready--to--Code-blue?logo=gitpod)](https://gitpod.io/#https://github.com/devlights/try-golang) 
+[![PkgGoDev](https://pkg.go.dev/badge/github.com/devlights/try-golang)](https://pkg.go.dev/github.com/devlights/try-golang)
 
 ## GO version