fix: typo correction (#1924)

* fix: typo correction

* fix: replace magic string with constant
diff --git a/config/reference_config.go b/config/reference_config.go
index f370691..c53bc52 100644
--- a/config/reference_config.go
+++ b/config/reference_config.go
@@ -192,7 +192,7 @@
 	invokers := make([]protocol.Invoker, len(rc.urls))
 	for i, u := range rc.urls {
 		if u.Protocol == constant.ServiceRegistryProtocol {
-			invoker = extension.GetProtocol("registry").Refer(u)
+			invoker = extension.GetProtocol(constant.RegistryProtocol).Refer(u)
 		} else {
 			invoker = extension.GetProtocol(u.Protocol).Refer(u)
 		}
diff --git a/remoting/xds/error.go b/remoting/xds/error.go
index 2711cf7..29c899c 100644
--- a/remoting/xds/error.go
+++ b/remoting/xds/error.go
@@ -22,6 +22,6 @@
 )
 
 var (
-	DiscoverLocalError       = errors.New("Discovery local Pod's host from xds, failed please register service with endpoint to k8s ")
+	DiscoverLocalError       = errors.New("Discovery local Pod's host from xds failed, please register service with endpoint to k8s ")
 	DiscoverIstiodPodIpError = errors.New("Discovery istiod Pod's ip from xds failed, please register service with endpoint to k8s ")
 )