Whitelist CTS test to allow bg wifi scans

Background wifi scans are now throttled, which would cause this CTS test
to break (unless it is allowed to run for a very long time). This
prevents the throttling for the CTS test app.

Bug: 37748887
Test: run cts-dev -m CtsIncidentHostTestCases -t com.android.server.cts.BatteryStatsValidationTest#testWifiScans
Change-Id: Idfdb1bea05665f4728755d29f9e2ff0645c20271
1 file changed