Remove setting of TLS max Version TLS1.2

This was only added for debugging and accidentally commited.

main.go

@@ -228,7 +228,6 @@ func main() {
 		fmt.Println("Unknown TLS version.")
 		os.Exit(0)
 	}
-	tlsConfig.MaxVersion = tls.VersionTLS12
 
 	// Check whether an authentification mechanism is pinned.
 	authMech, _ := parsePinFile(user)