ostree: Fix bug printing out commit body
ostree: Fix bug printing out commit body

Body was printed out repeated and mangled due to bad printf format string.

https://bugzilla.gnome.org/show_bug.cgi?id=707067

sujitfulse/ostree,sujitfulse/ostree,gatispaeglis/ostree,leandrosansilva/ostree,resin-io/ostree,GNOME/ostree,leandrosansilva/ostree,GNOME/ostree,gatispaeglis/ostree,leandrosansilva/ostree,leandrosansilva/ostree,resin-io/ostree,gatispaeglis/ostree,resin-io/ostree,GNOME/ostree,gatispaeglis/ostree,resin-io/ostree,GNOME/ostree,resin-io/ostree,gatispaeglis/ostree,gatispaeglis/ostree,sujitfulse/ostree,GNOME/ostree,sujitfulse/ostree,leandrosansilva/ostree,sujitfulse/ostree