Fixes nulls in managed_overlays (#60323)
Fixes nulls in managed_overlays (#60323)

#60320 highlighted an issue about managed_overlays, this fixes a null i noticed some time ago in them
Jordie0608/tgstation,MicroWorldwide/SS13-TG-station,coiax/-tg-station,MicroWorldwide/SS13-TG-station,Jordie0608/tgstation,Cruix/-tg-station,ShizCalev/tgstation,Bawhoppen/-tg-station,tgstation/tgstation,tgstation/tgstation,MicroWorldwide/SS13-TG-station,tgstation/tgstation,Razharas/-tg-station,Cruix/-tg-station,MicroWorldwide/SS13-TG-station,WJohn/-tg-station,tgstation/-tg-station,CPTANT/-tg-station,Jordie0608/tgstation,WJohn/-tg-station,WJohn/-tg-station,tgstation/-tg-station,CPTANT/-tg-station,coiax/-tg-station,Razharas/-tg-station,Bawhoppen/-tg-station,Jordie0608/tgstation,MicroWorldwide/SS13-TG-station,CPTANT/-tg-station,Cruix/-tg-station,CPTANT/-tg-station,Bawhoppen/-tg-station,ShizCalev/tgstation,MicroWorldwide/SS13-TG-station,ShizCalev/tgstation,Bawhoppen/-tg-station,tgstation/-tg-station,WJohn/-tg-station,coiax/-tg-station,Razharas/-tg-station,Cruix/-tg-station,coiax/-tg-station,Cruix/-tg-station,MicroWorldwide/SS13-TG-station,Cruix/-tg-station,coiax/-tg-station,WJohn/-tg-station,CPTANT/-tg-station,Razharas/-tg-station,coiax/-tg-station,Bawhoppen/-tg-station,ShizCalev/tgstation,Bawhoppen/-tg-station,tgstation/tgstation,tgstation/tgstation,coiax/-tg-station,ShizCalev/tgstation,tgstation/-tg-station,Jordie0608/tgstation,CPTANT/-tg-station,Razharas/-tg-station,MicroWorldwide/SS13-TG-station,ShizCalev/tgstation,Bawhoppen/-tg-station,Razharas/-tg-station,CPTANT/-tg-station,tgstation/tgstation,Bawhoppen/-tg-station,Jordie0608/tgstation,ShizCalev/tgstation,tgstation/tgstation,tgstation/tgstation,Jordie0608/tgstation,Cruix/-tg-station,Razharas/-tg-station,Jordie0608/tgstation,Cruix/-tg-station,ShizCalev/tgstation,CPTANT/-tg-station,WJohn/-tg-station,Razharas/-tg-station,WJohn/-tg-station