fix: test the creating of traceID with customer randomNum func

Signed-off-by: guanwenbo <guanwenbostar@163.com>

config/config_test.go

@@ -901,11 +901,17 @@ func TestThrottlerDefaultConfig(t *testing.T) {
 }
 
 func TestWithRandomNumber(t *testing.T) {
+	const traceID uint64 = 1
+
 	cfg := &Configuration{
 		ServiceName: "test-random-number",
 	}
-	randomNum := func() uint64 { return 1 }
-	_, closer, err := cfg.NewTracer(WithRandomNumber(randomNum))
+	randomNum := func() uint64 { return traceID }
+	tracer, closer, err := cfg.NewTracer(WithRandomNumber(randomNum))
+	span:=tracer.StartSpan("test-span")
+	spanCtx := span.Context().(jaeger.SpanContext)
+
 	assert.NoError(t, err)
+	assert.Equal(t, spanCtx.TraceID().Low ,traceID)
 	defer closeCloser(t, closer)
 }