Remove Connect/Disconnect button dependence on WifiEntry.isExpired()

WifiEntry.canConnect() may be true even if isExpired() is true, such as
in the case of connecting to renew a subscription. Thus, the
connect/disconnect button should only rely on canConnect() and
canDisconnect() (as well as the intermediate state of connecting) to
determine its visibility.

Bug: 150384136
Test: manually install expired passpoint profile and verify if the
connect button is visible and working.

Change-Id: Ibfdf285f3b97fd0de88804d4658df20bd67bf8e0