Fixes a typo that made the game think there's not a CO onboard. (#3722)

# About the pull request

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Officer, not Officers

# Explain why it's good for the game
# Testing Photographs and Procedure
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bugs bad

# Changelog
:cl:
fix: The game will no longer falsely claim there is no CO
/:cl:

---------

Co-authored-by: harryob <[email protected]>

code/controllers/subsystem/ticker.dm

@@ -424,7 +424,7 @@ SUBSYSTEM_DEF(ticker)
 
 	for(var/mob/living/carbon/human/player in GLOB.human_mob_list)
 		if(player.mind)
-			if(player.job == "Commanding Officers")
+			if(player.job == JOB_CO)
 				captainless = FALSE
 			if(player.job)
 				RoleAuthority.equip_role(player, RoleAuthority.roles_by_name[player.job], late_join = FALSE)