remove getter for physics components which causes compilation errors with gcc...

remove getter for physics components which causes compilation errors with gcc because of auto return type deduction

include/physics/physics_system.h

@@ -32,10 +32,6 @@ public:
 		return collision_data_manager_;
 	}
 
-	auto& collision_components() {
-		return collision_components_;
-	}
-
 private:
 	void register_movement_component(movement_component* comp);
 	void unregister_movement_component(movement_component* comp);