Thanks for reporting @shaddeen!
We’ll fix this asap, in the meantime can you please try this workaround? Xcode 9 GM - Failed to create target code sign properties mapping, error
Let us know if that wouldn’t help or if you have any questions! 
Thanks for reporting @shaddeen!
We’ll fix this asap, in the meantime can you please try this workaround? Xcode 9 GM - Failed to create target code sign properties mapping, error
Let us know if that wouldn’t help or if you have any questions! 