Fix launcher potential null reference (#6567)
Fix launcher potential null reference (#6567)

- Fix launcher potential null reference if the job is null
AlexCatarino/Lean,AlexCatarino/Lean,AlexCatarino/Lean,QuantConnect/Lean,AlexCatarino/Lean,QuantConnect/Lean,QuantConnect/Lean,QuantConnect/Lean