[#9999] rpc: Fix mem leak again

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

api/rpc/client/stream_wrapper.go

@@ -2,7 +2,6 @@ package client
 
 import (
 	"context"
-	"sync"
 	"time"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/api/rpc/message"
@@ -11,12 +10,11 @@ import (
 
 type streamWrapper struct {
 	grpc.ClientStream
-	timeout       time.Duration
-	cancel        context.CancelFunc
-	closeSendOnce sync.Once
+	timeout time.Duration
+	cancel  context.CancelFunc
 }
 
-func (w *streamWrapper) ReadMessage(m message.Message) error {
+func (w streamWrapper) ReadMessage(m message.Message) error {
 	// Can be optimized: we can create blank message here.
 	gm := m.ToGRPCMessage()
 
@@ -30,20 +28,14 @@ func (w *streamWrapper) ReadMessage(m message.Message) error {
 	return m.FromGRPCMessage(gm)
 }
 
-func (w *streamWrapper) WriteMessage(m message.Message) error {
+func (w streamWrapper) WriteMessage(m message.Message) error {
 	return w.withTimeout(func() error {
 		return w.ClientStream.SendMsg(m.ToGRPCMessage())
 	})
 }
 
 func (w *streamWrapper) closeSend() error {
-	var err error
-	w.closeSendOnce.Do(
-		func() {
-			err = w.withTimeout(w.ClientStream.CloseSend)
-		},
-	)
-	return err
+	return w.withTimeout(w.ClientStream.CloseSend)
 }
 
 func (w *streamWrapper) Close() error {