Correct detail page UI once user change MAC randomized setting

Changing MAC randomized setting will disconnect and reconnect Wi-Fi in
the background automatically. UI display as disconnect even AP
reconnected. Fix this problem and also remove some obsolete code.
Another problem is connect button display as disabled with
"Connecting..." wording after user click connect then change the MAC
randomized setting.

Bug: 130370187
Test: Manual test with test case in go/wifi_connnection_btn_design
Test: make RunSettingsRoboTests -j32 ROBOTEST_FILTER=com.android.settings.wifi.details.WifiDetailPreferenceControllerTest
Change-Id: Id87c3db0cc785a9ceb3a71c7cbb78ffd87ffb0a1