add test for binance new function

pkg/exchange/binance/exchange_test.go

@@ -1,6 +1,7 @@
 package binance
 
 import (
+	"context"
 	"strings"
 	"testing"
 
@@ -15,3 +16,12 @@ func Test_newClientOrderID(t *testing.T) {
 	cID = newSpotClientOrderID("myid1")
 	assert.Equal(t, cID, "x-"+spotBrokerID+"myid1")
 }
+
+func Test_new(t *testing.T) {
+	ex := New("", "")
+	assert.NotEmpty(t, ex)
+	ctx := context.Background()
+	ticker, err := ex.QueryTicker(ctx, "btcusdt")
+	assert.NotEmpty(t, ticker)
+	assert.NoError(t, err)
+}