docs: fix comment (#4205)

Co-authored-by: voyager1 <voyager1@voyager1deMacBook-Pro.local>

binding/protobuf.go

@@ -34,7 +34,7 @@ func (protobufBinding) BindBody(body []byte, obj any) error {
 	if err := proto.Unmarshal(body, msg); err != nil {
 		return err
 	}
-	// Here it's same to return validate(obj), but util now we can't add
+	// Here it's same to return validate(obj), but until now we can't add
 	// `binding:""` to the struct which automatically generate by gen-proto
 	return nil
 	// return validate(obj)