Fix docstring typo in numba/cuda/testing.py
Fix docstring typo in numba/cuda/testing.py

Co-Authored-By: stuartarchibald <bea6903cc29f240e46cd18ca8cb3cffc8245594f@users.noreply.github.com>
cpcloud/numba,seibert/numba,gmarkall/numba,numba/numba,IntelLabs/numba,stuartarchibald/numba,stonebig/numba,numba/numba,cpcloud/numba,stuartarchibald/numba,sklam/numba,IntelLabs/numba,sklam/numba,IntelLabs/numba,cpcloud/numba,stuartarchibald/numba,numba/numba,gmarkall/numba,stuartarchibald/numba,stuartarchibald/numba,stonebig/numba,numba/numba,sklam/numba,gmarkall/numba,stonebig/numba,seibert/numba,IntelLabs/numba,stonebig/numba,seibert/numba,gmarkall/numba,numba/numba,cpcloud/numba,seibert/numba,IntelLabs/numba,seibert/numba,sklam/numba,cpcloud/numba,stonebig/numba,gmarkall/numba,sklam/numba