Stop hiding suggestion once `requestDeviceSuggestion` is called.

Before:
- Hide the device suggestion after showing the suggestion with
CONNECTION_FAILED state for 20 seconds.
- Show the device suggestion if available on receiving
`onSuggestedDeviceStateUpdated` callback.

After:
- Hide the device suggestion after showing the suggestion with
CONNECTION_FAILED state for 20 seconds.
- Show the device suggestion on making `requestDeviceSuggestion` call.

The former approach was error-prone because the
`onSuggestedDeviceStateUpdated` callback might never be called if the
suggested route remains unchanged.

Fix: 442626602
Test: atest SuggestedDeviceManagerTest
Flag: EXEMPT BUGFIX
Change-Id: I6e8f17cffe931f10f2292f1854fd6a71c8cb2719