Add config flow support to google_travel_time (#43509)

* add config flow support to google_travel_time

* fix bugs and add strings

* fix import and add new test

* address comments in #43419 since this is a similar PR

* fix default name and test

* add unique ID and device info

* fix test

* feedback from waze PR

* continue incorporating feedback from waze PR

* final fixes and update tests

* call update in lambda

* Update homeassistant/components/google_travel_time/sensor.py

Co-authored-by: Martin Hjelmare <marhje52@gmail.com>

* additional fixes

* validate config entry data during config flow and config entry setup

* don't store entity

* patch dependency instead of HA code

* fixes

* improve tests by moving all patching to fixtures

* use self.hass instead of setting self._hass

* invert if

* remove unnecessary else

Co-authored-by: Martin Hjelmare <marhje52@gmail.com>