Fix typo in function name (#7982)
Fix typo in function name (#7982)

no issue
- checkDirectoryExistance -> checkDirectoryExistence
kevinansfield/Ghost,mohanambati/Ghost,ErisDS/Ghost,dbalders/Ghost,singular78/Ghost,mohanambati/Ghost,leninhasda/Ghost,BlueHatbRit/Ghost,Kikobeats/Ghost,letsjustfixit/Ghost,Kikobeats/Ghost,dbalders/Ghost,stridespace/Ghost,e10/Ghost,Kikobeats/Ghost,sebgie/Ghost,acburdine/Ghost,sebgie/Ghost,TryGhost/Ghost,ErisDS/Ghost,cwonrails/Ghost,singular78/Ghost,bitjson/Ghost,janvt/Ghost,novaugust/Ghost,e10/Ghost,leninhasda/Ghost,ErisDS/Ghost,kevinansfield/Ghost,stridespace/Ghost,dbalders/Ghost,JohnONolan/Ghost,TryGhost/Ghost,sebgie/Ghost,JohnONolan/Ghost,bitjson/Ghost,stridespace/Ghost,cwonrails/Ghost,vainglori0us/urban-fortnight,vainglori0us/urban-fortnight,singular78/Ghost,janvt/Ghost,chevex/undoctrinate,acburdine/Ghost,letsjustfixit/Ghost,BlueHatbRit/Ghost,Gargol/Ghost,novaugust/Ghost,letsjustfixit/Ghost,SkynetInc/steam,Gargol/Ghost,mohanambati/Ghost,cwonrails/Ghost,vainglori0us/urban-fortnight,acburdine/Ghost,TryGhost/Ghost,novaugust/Ghost,kevinansfield/Ghost,SkynetInc/steam,JohnONolan/Ghost