Fix NRE when magazineless weapon runs out of ammo

[Thorbane]

Changes

• Add null check against current job before attempting to suspend it

References

• https://discord.com/channels/278818534069501953/324222101550661663/1453616740708782194

Reasoning

• Stops error messages from occurring when a bow or other magzineless ammo using weapon runs out of ammo

Alternatives

• Use a different method than the brute force suspend job?

Testing

Check tests you have performed:

• Compiles without warnings
• Game runs without errors
• (For compatibility patches) ...with and without patched mod loaded
• Playtested a colony (2 minutes)

[github-actions]

You can download the rebuilt assembly for this PR here: https://combatextended.lp-programming.com/CombatExtended-20517086884.zip