Refactor Evaluator & Adapt Scenarios

[patrickhart]

Changes:

• Use SingleTrackSteeringRateModel as dynamic modle in the single_lane scenario
• Adapt the StaticObserver using the new state space of the dynamic model
• Add a boolean state to the StaticObserver whether it is on the goal or not
• Implement PotentialGoalSwitchVelocityFunctor that switches the desired velocity based on being inside the goal
• Episodes are non-terminal in the single_lane scenario when reaching the goal
• Adapt the blueprints to work with the new evaluators based on the GeneralEvaluator