Send the network logging enabled notification to the current user.

It was sending it to the system user, which wouldn't work on systems
with headless system user.

Test: atest FrameworksServicesTests:DevicePolicyManagerTest
Test: manual verification with TestDpc and CtsVerifier on phone and automotive
Test: adb shell dumpsys device_policy | grep mNetworkLoggingNotificationUserId

Bug: 205190291

Change-Id: I0c060a9d9f1c41f63f9bcebd3c1848963ff12764