Merge pull request #6383 from gyuho/lease-client

clientv3: use correct context in toErr (lease)

clientv3/lease.go

@@ -141,7 +141,7 @@ func (l *lessor) Grant(ctx context.Context, ttl int64) (*LeaseGrantResponse, err
 			return gresp, nil
 		}
 		if isHaltErr(cctx, err) {
-			return nil, toErr(ctx, err)
+			return nil, toErr(cctx, err)
 		}
 		if nerr := l.newStream(); nerr != nil {
 			return nil, nerr