CONFIGURED_NETWORKS_CHANGED_ACTION: update docs since we stop sending WifiConfiguration

WifiConfiguration contains sensitive location
information, so this extra is no longer included
in the CONFIGURED_NETWORKS_CHANGED_ACTION
broadcast. Update docs to reflect this change.

Bug: 158874479
Test: compiles
Change-Id: I72ba9f75a89519ef136cc2766a8551b606b218c7