Update Gesture navigation tutorial to match new specs

- Updated strings
- Updated removed 'next' button when there are followign steps
- Added timeout to automatically continue the tutorial
- Combined back left and right into one step

Bug: 192009114
Bug: 177005427
Test: manual
Change-Id: I58b9017c4d69b5d097326c7d5be156a63951fb1a

quickstep/src/com/android/quickstep/interaction/HomeGestureTutorialController.java

@@ -82,7 +82,6 @@ final class HomeGestureTutorialController extends SwipeUpGestureTutorialControll
                     case HOME_GESTURE_COMPLETED: {
                         mTutorialFragment.releaseGestureVideoView();
                         animateFakeTaskViewHome(finalVelocity, null);
-                        showActionButton();
                         int subtitleResId = mTutorialFragment.isAtFinalStep()
                                 ? R.string.home_gesture_feedback_complete_without_follow_up
                                 : R.string.home_gesture_feedback_complete_with_follow_up;