public static void refreshTargetServiceInstances(String serviceName) {
        refreshTargetServiceInstances(serviceName, null);
    }
@Test
    public void refreshTargetServiceInstances() {
        try (final MockedStatic<PluginConfigManager> pluginConfigManagerMockedStatic = Mockito.mockStatic(PluginConfigManager.class);){
            pluginConfigManagerMockedStatic.when(() -> PluginConfigManager.getPluginConfig(GraceConfig.class))
                    .thenReturn(new GraceConfig());
            testRibbon();
            testSpringLb();
        }

    }