Update README.md

Author: BoRuDar

README.md

@@ -1,7 +1,7 @@
 [![Go Report Card](https://goreportcard.com/badge/github.com/borudar/configuration)](https://goreportcard.com/report/github.com/borudar/configuration)
 [![codecov](https://codecov.io/gh/BoRuDar/configuration/branch/master/graph/badge.svg)](https://codecov.io/gh/BoRuDar/configuration)
 ![Go](https://github.com/BoRuDar/configuration/workflows/Go/badge.svg)
-[![GoDoc](https://godoc.org/github.com/BoRuDar/configuration?status.png)](https://godoc.org/github.com/BoRuDar/configuration/v3)
+[![GoDoc](https://godoc.org/github.com/BoRuDar/configuration?status.png)](https://godoc.org/github.com/BoRuDar/configuration/v4)
 [![Mentioned in Awesome Go](https://awesome.re/mentioned-badge.svg)](https://github.com/avelino/awesome-go) 
 
 # Configuration