Add polling for WifiManager#getConnectionInfo

In Cts test after disabling Wifi, the WifiManager#getConnectionInfo will
not return network id -1 immediately. Need to poll the wifi disabled and
the network connection info cleared before asserting the connection
info.

Bug: 252869312
Test: atest ConnectivityManagerTest#testRejectPartialConnectivity_TearDownNetwork
Change-Id: If88261b0d81c1dc1731c683513878d054d2cb0dc
3 files changed