Sidetrack2: remove busy loop to wait for toyapp

New toy app register their dbus name after the JS application
is loaded so there is no need to busy wait for it.

https://phabricator.endlessm.com/T29266

eosclubhouse/quests/hack2/sidetrack2.py

@@ -27,23 +27,7 @@ def step_begin(self):
         self.ask_for_app_launch(message_id='LAUNCH')
 
         highest_level = self._app.get_js_property('highestAchievedLevel')
-
-        # @fixme: This is a workaround to https://phabricator.endlessm.com/T29180
-        # Sometimes Sidetrack app takes lot of time to start and get_js_property times out.
-        if highest_level is None:
-            logger.debug('Quest %s: Cannot get \'highestAchievedLevel\' for %s. Trying again...',
-                         self.get_id(), self.app.dbus_name)
-            return self.step_begin
-
-        # This is a workaround to wait until the sidetrack app reads the
-        # information from the game state service. In the future we should add
-        # a signal or a property to the toyapps and move this wait to a new
-        # method in Quest
         current_level = int(self._app.get_js_property('currentLevel'))
-        while current_level == 0:
-            logger.debug(f'Current level is 0, waiting for sidetrack to load data')
-            self.pause(1)
-            current_level = self._app.get_js_property('currentLevel')
 
         if highest_level < 23 or highest_level > 28:
             self._app.set_js_property('highestAchievedLevel', ('u', 23))