Waiting for idle in test

Waiting for idle in testRequestsSortedByIdSortsCorrectly to give it time
to handle async operations as part of registering network callbacks.

Bug: 177376544
Test: atest FrameworksNetTests:ConnectivityServiceTest#
testRequestsSortedByIdSortsCorrectly --rerun-until-failure 200

Change-Id: I268c4607d1a4c79e79f1385f014563cea0c2f979
1 file changed