debugDraw runs in builds

[tonygiang]

While profiling a game using this library on a real device, I spotted this:

The debugDraw coroutine in MovementAIRigidbody will take up more time per frame during more crowded segments, sometimes consuming nearly 1ms per frame. This should not be happening. Ideally, this coroutine should only be run inside an #if UNITY_EDITOR block.