nvcc warnings are not caught in testing

Created by: aprokop

Detected in #268. Warnings like

/var/jenkins/workspace/ArborX_PR-268/src/details/ArborX_Predicates.hpp(34): warning: __device__ annotation is ignored on a function("Nearest") that is explicitly defaulted on its first declaration

were not detected in Style. It seems that there is problematic interaction of nvcc_wrapper, nvcc, jenkins, etc.