chore(README): update badge to use v2

Author: kkweon

Diff for: README.md

@@ -2,7 +2,7 @@
 
 [![Go](https://github.com/codingpot/paperswithcode-go/v2/actions/workflows/go.yaml/badge.svg)](https://github.com/codingpot/paperswithcode-go/v2/actions/workflows/go.yaml)
 [![Go Report Card](https://goreportcard.com/badge/github.com/codingpot/paperswithcode-go)](https://goreportcard.com/report/github.com/codingpot/paperswithcode-go)
-[![Go Reference](https://pkg.go.dev/badge/github.com/codingpot/paperswithcode-go.svg)](https://pkg.go.dev/github.com/codingpot/paperswithcode-go)
+[![Go Reference](https://pkg.go.dev/badge/github.com/codingpot/paperswithcode-go/v2.svg)](https://pkg.go.dev/github.com/codingpot/paperswithcode-go/v2)
 [![codecov](https://codecov.io/gh/codingpot/paperswithcode-go/branch/main/graph/badge.svg?token=MhzDKZOtWK)](https://codecov.io/gh/codingpot/paperswithcode-go)
 
 This is a client for PapersWithCode read/write API.
@@ -19,4 +19,4 @@ import "github.com/codingpot/paperswithcode-go"
 c := paperswithcode_go.NewClient()
 papers, _ := c.PaperList(paperswithcode_go.PaperListParamsDefault())
 gan, _ := c.PaperGet(paperswithcode_go.GetPaperIDFromPaperTitle("Generative Adversarial Networks"))
-```
+```