Repro steps:
1. Open attached project
2. Build and Run on an ARKit not capable device
3. Check the log output in XCode

Actual: An "NotSupportedException: Update requires a configuration. at UnityEngine.XR.ARKit.ARKitSessionSubsystem+ARKitProvider.Update (UnityEngine.XR.ARSubsystems.XRSessionUpdateParams updateParams)" exception thrown

Reproducible with: ARFoundation & ARKit 4.0.2

Tested and reproduced on these devices:
iPad Air 2 (iOS 11.0.3)

Did not reproduce on:
VLNQA00013, Samsung Galaxy S6 edge+ (SM-G928F), Android 7.0, CPU: Exynos 7 Octa 7420, GPU: Mali-T760
VLNQA00078, Motorola Nexus 6 (Nexus 6), Android 7.1.1, CPU: Snapdragon 805 APQ8084AB, GPU: Adreno (TM) 420
iPhone 5C (iOS 10.3.3)