MetricsProviderTest: add assertion about NETWORK_TOTAL_BYTES_IN and NETWORK_TOTAL_BYTES_OUT

Author: eolivelli

tests/src/test/java/io/streamnative/pulsar/handlers/kop/MetricsProviderTest.java

@@ -230,6 +230,10 @@ public void testMetricsProvider() throws Exception {
         Assert.assertTrue(sb.toString().contains("kop_server_PRODUCE_MESSAGE_CONVERSIONS{partition=\"0\","
                 + "topic=\"kopKafkaProducePulsarMetrics1\"} 10"));
         Assert.assertTrue(sb.toString().contains("kop_server_PRODUCE_MESSAGE_CONVERSIONS_TIME_NANOS"));
+
+        // network stats
+        Assert.assertTrue(sb.toString().contains("NETWORK_TOTAL_BYTES_IN"));
+        Assert.assertTrue(sb.toString().contains("NETWORK_TOTAL_BYTES_OUT"));
     }
 
     @Test(timeOut = 20000)