Where are the Provisioning Profiles located in Xcode 8.3.3 within the project and/or file directory?
~/Library/MobileDevice/Provisioning Profiles
Where they have been for older versions of Xcode: ~/Library/MobileDevice/Provisioning\ Profiles
Provisioning profiles are not stored with the project. Xcode has a common area and the profile is pulled when you build and bundled with the ipa.