GraspPlanResult's retract_result returns None on success

[jsupratman13]

If it’s not a bug, please use discussions: https://github.com/NVlabs/curobo/discussions

Please provide the below information in addition to your issue:

1. cuRobo installation mode (choose from [python, isaac sim, docker python, docker isaac sim]): python
2. python version: python 3.8.10
3. Isaac Sim version (if using):

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Issue Details

retract_result returns None, when planning is successful.
Based on how approach_result/grasp_result is written,

result.retract_result = retract_grasp_mg_result

I believe the code above should be inserted between the line below

curobo/src/curobo/wrap/reacher/motion_gen.py

Lines 4415 to 4416 in 2fbffc3

	result.planning_time += retract_grasp_mg_result.total_time
	if not retract_grasp_mg_result.success.item():