docs: update mod url

Author: rehiy

README.md

@@ -5,6 +5,7 @@ This package implements the [libdns](https://github.com/libdns/libdns) interface
 ## Code example
 
 ```shell
+import "github.com/libdns/tencentcloud"
 provider := &tencentcloud.Provider{
     SecretId:  "YOUR_Secret_ID",
     SecretKey: "YOUR_Secret_Key",

_example/main.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"fmt"
 
-	tencentcloud "github.com/libdns/tencentcloud"
+	"github.com/libdns/tencentcloud"
 )
 
 func main() {