Update README.md

Author: shaj13

README.md

@@ -36,6 +36,7 @@ Here are a few bullet point reasons you might like to try it out:
 
 ## Strategies
 * [kubernetes (Token Review)](https://pkg.go.dev/github.com/shaj13/go-guardian/auth/strategies/kubernetes?tab=doc)
+* [2FA](https://pkg.go.dev/github.com/shaj13/go-guardian/auth/strategies/twofactor?tab=doc)
 * [Certificate-Based](https://pkg.go.dev/github.com/shaj13/[email protected]/auth/strategies/x509?tab=doc)
 * [Bearer-Token](https://pkg.go.dev/github.com/shaj13/[email protected]/auth/strategies/bearer?tab=doc)
 * [Static-Token](https://pkg.go.dev/github.com/shaj13/[email protected]/auth/strategies/bearer?tab=doc)