wifi: update connectable networks for user selected networks

Network selection is run based on connectable networks, but they are
not updated properly.

As connectable networks are stored internally, moving getCandidatesForUserSelection()
to WifiNetworkSector to update connectable networks.

Bug: 225259099
Test: atest FrameworksWifiTests
      connect to a network manually and check network selection is run
Change-Id: I9e3fa9cedf60638c0c15c6d884ea6728c997d85b
3 files changed