Fixed correct promise order in RSS feed generator (#9726)
Fixed correct promise order in RSS feed generator (#9726)

no issue

- the 'rss.feed' filter used to get an empty feed as a parameter, because item generation is done via promises
- now it waits until all items have been added

kevinansfield/Ghost,ErisDS/Ghost,ErisDS/Ghost,Kikobeats/Ghost,TryGhost/Ghost,Kikobeats/Ghost,bitjson/Ghost,e10/Ghost,janvt/Ghost,TryGhost/Ghost,JohnONolan/Ghost,janvt/Ghost,JohnONolan/Ghost,Gargol/Ghost,kevinansfield/Ghost,TryGhost/Ghost,bitjson/Ghost,ErisDS/Ghost,e10/Ghost,kevinansfield/Ghost,Gargol/Ghost,JohnONolan/Ghost,Kikobeats/Ghost