manifest: Update webkitgtk, and untag gnome-online-accounts/epiphany
manifest: Update webkitgtk, and untag gnome-online-accounts/epiphany

vrutkovs/vrutkovs.github.io,GNOME/gnome-ostree,GNOME/gnome-ostree,GNOME/gnome-ostree,vrutkovs/vrutkovs.github.io,chergert/gnome-continuous,vrutkovs/vrutkovs.github.io,chergert/gnome-continuous,chergert/gnome-continuous