Fixes a runtime in PDA gas scanner code

[silverplatedelta]

What Does This PR Do

Fixes a null value runtime in PDA atmos scanner code

Why It's Good For The Game

Runtime bad

Testing

Compiles, now gives a readout when scanning empty pipes

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Declaration

• I confirm that I either do not require pre-approval for this PR, or I have obtained such approval and have included a screenshot to demonstrate this below.

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Changelog

🆑
fix: PDA atmos scanners no longer runtime when scanning empty devices.
/:cl:

[chuga-git]

Suggested change

	total_moles += air?.total_moles()
	volume += air?.return_volume()
	heat_capacity += air?.heat_capacity()
	thermal_energy += air?.thermal_energy()
	oxygen += air?.oxygen()
	nitrogen += air?.nitrogen()
	toxins += air?.toxins()
	carbon_dioxide += air?.carbon_dioxide()
	sleeping_agent += air?.sleeping_agent()
	agent_b += air?.agent_b()
	if(!air)
	continue
	total_moles += air.total_moles()
	volume += air.return_volume()
	heat_capacity += air.heat_capacity()
	thermal_energy += air.thermal_energy()
	oxygen += air.oxygen()
	nitrogen += air.nitrogen()
	toxins += air.toxins()
	carbon_dioxide += air.carbon_dioxide()
	sleeping_agent += air.sleeping_agent()
	agent_b += air.agent_b()

If air is non-null, all of these procs are valid calls.