wifi data usage: replaced Wi-Fi SSID with a Wi-Fi network key

1. Used SSID to be a wifi network identity can't separate wifi
data usage when there are two different network with same SSID.
Use a new usage key from WifiInfo to replace wifi SSID to solve
this issue.

2. To support to query wifi usage per configured Wifi network.
Adding matchWifiNetworkKeys in NetworkTemplate to support querying
multi networkKeys wifi data usage since each configured Wifi
network configuration might be used to connect different Wifi
network. (Replace mNetworkId with mMatchWifiNetworkKeys)

3. Updated callers who were using NetworkTemplate constructor.

4. Fixed SortedSet null order case. The null subscriberId is a
valid input for matchSubscriberIds.

5. Replaced ArrayUtils with CollectionUtils.

Bug: 197520752
Bug: 126299427
Test: atest -c NetworkTemplateTest
Test: atest -c NetworkStatsServiceTest
Test: atest -c NetworkPolicyManagerServiceTest
Test: atest -c NetworkPolicyTest
Change-Id: Ie20e7fb56597817901be4ce1d2a7afcbc9ded0c6