Fixed usage of bson-objectid
Fixed usage of bson-objectid

no-issue

Calling ObjectId doesn't return a string a but an ObjectId object.
Whilst this object is cast to a string via the toJSON and toString
methods, this is not enough for MySQL. Instead we should explicitly cast
this to a string ourselves and the application level.

TryGhost/Ghost,TryGhost/Ghost,TryGhost/Ghost