wifi: Use new API for wifi data usage function

For wifi, a old API: buildTemplateWifiWildcard will includes the merged
wifi which is included to mobile usage. It should not double count
again. Call new API: buildTemplateWifi with
NetworkId: NetworkTemplate.WIFI_NETWORKID_ALL
and null subscriberId to get non-merged wifi usage.

Test: make RunSettingsRoboTests ROBOTEST_FILTER=AppDataUsageTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=AppDataUsagePreferenceControllerTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=DataUsageSummaryTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=DataUsageSummaryPreferenceTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=DataUsageSummaryPreferenceControllerTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=DataUsageUtilsTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=NetworkProviderSettingsTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=SettingsDumpServiceTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=WifiSettingsTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=DataUsageInfoControllerTest
Test: Manual Test, wifi data usage count correctly.
Bug: 176396812
Change-Id: Ia4d8fa67ea3cb75c2d35be9ab60e5c5ffa391ffb