[Provider Model] Add Fix connectivity toggle to Internet Settings

- Add Fix connectivity toggle in menu item

- Show "Resetting your internet..." when recovering

- Screenshot:
  https://screenshot.googleplex.com/BPyRADfNUoPE8Dc

Bug: 172297799
Test: manual test
- make RunSettingsRoboTests ROBOTEST_FILTER=NetworkProviderSettingsTest

Change-Id: I27594d24659ca281e224f86accc20d49514d5001