Fix _run_cupy

[thuydotm]

Fixes for issue #159

======================================================================================= test session starts ========================================================================================
platform win32 -- Python 3.7.4, pytest-5.2.1, py-1.8.0, pluggy-0.13.0
rootdir: D:\xarray-spatial
plugins: arraydiff-0.3, doctestplus-0.4.0, openfiles-0.4.0, remotedata-0.3.2
collected 83 items

test_aspect.py ....                                                                                                                                                                           [  4%]
test_bump.py .                                                                                                                                                                                [  6%]
test_classify.py ....                                                                                                                                                                         [ 10%]
test_curvature.py ....                                                                                                                                                                        [ 15%]
test_focal.py ....                                                                                                                                                                            [ 20%]
test_hillshade.py ..                                                                                                                                                                          [ 22%]
test_multispectral.py ....................                                                                                                                                                    [ 46%]
test_pathfinding.py .                                                                                                                                                                         [ 48%]
test_perlin.py .                                                                                                                                                                              [ 49%]
test_proximity.py .....                                                                                                                                                                       [ 55%]
test_slope.py .....                                                                                                                                                                           [ 61%]
test_terrain.py .                                                                                                                                                                             [ 62%]
test_tiles.py ....                                                                                                                                                                            [ 67%]
test_viewshed.py ....                                                                                                                                                                         [ 72%]
test_zonal.py .......................                                                                                                                                                         [100%]

========================================================================================= warnings summary =========================================================================================
C:\Users\mdo\Anaconda3\lib\site-packages\win32\lib\pywintypes.py:2
  C:\Users\mdo\Anaconda3\lib\site-packages\win32\lib\pywintypes.py:2: DeprecationWarning: the imp module is deprecated in favour of importlib; see the module's documentation for alternative uses
    import imp, sys, os

C:\Users\mdo\Anaconda3\lib\site-packages\numba\cuda\envvars.py:16
  C:\Users\mdo\Anaconda3\lib\site-packages\numba\cuda\envvars.py:16: NumbaDeprecationWarning:
  Environment variables with the 'NUMBAPRO' prefix are deprecated, found use of NUMBAPRO_NVVM=C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v10.2\nvvm\bin\nvvm64_33_0.dll.

  For more information visit http://numba.pydata.org/numba-doc/latest/reference/deprecation.html#deprecation-of-numbapro-environment-variables
    warnings.warn(errors.NumbaDeprecationWarning(msg))

C:\Users\mdo\Anaconda3\lib\site-packages\numba\cuda\envvars.py:16
  C:\Users\mdo\Anaconda3\lib\site-packages\numba\cuda\envvars.py:16: NumbaDeprecationWarning:
  Environment variables with the 'NUMBAPRO' prefix are deprecated, found use of NUMBAPRO_LIBDEVICE=C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v10.2\nvvm\libdevice.

  For more information visit http://numba.pydata.org/numba-doc/latest/reference/deprecation.html#deprecation-of-numbapro-environment-variables
    warnings.warn(errors.NumbaDeprecationWarning(msg))

C:\Users\mdo\Anaconda3\lib\importlib\_bootstrap.py:219
  C:\Users\mdo\Anaconda3\lib\importlib\_bootstrap.py:219: RuntimeWarning: numpy.ufunc size changed, may indicate binary incompatibility. Expected 192 from C header, got 216 from PyObject
    return f(*args, **kwds)

xrspatial/tests/test_focal.py::test_kernel
xrspatial/tests/test_focal.py::test_convolution
xrspatial/tests/test_focal.py::test_hotspot
  D:\thuydo\upwork\xarray-spatial\xrspatial\focal.py:89: Warning: Raster distance unit not provided. Use meter as default.
    'Use meter as default.', Warning)

xrspatial/tests/test_focal.py::test_kernel
xrspatial/tests/test_focal.py::test_convolution
xrspatial/tests/test_focal.py::test_hotspot
  D:\thuydo\upwork\xarray-spatial\xrspatial\focal.py:51: Warning: Raster distance unit not provided. Use meter as default.
    'Use meter as default.', Warning)

xrspatial/tests/test_pathfinding.py::test_a_star_search
xrspatial/tests/test_pathfinding.py::test_a_star_search
xrspatial/tests/test_pathfinding.py::test_a_star_search
xrspatial/tests/test_pathfinding.py::test_a_star_search
xrspatial/tests/test_pathfinding.py::test_a_star_search
xrspatial/tests/test_pathfinding.py::test_a_star_search
xrspatial/tests/test_pathfinding.py::test_a_star_search
  D:\thuydo\upwork\xarray-spatial\xrspatial\pathfinding.py:310: Warning: End at a non crossable pixel
    warnings.warn('End at a non crossable pixel', Warning)

xrspatial/tests/test_pathfinding.py::test_a_star_search
xrspatial/tests/test_pathfinding.py::test_a_star_search
  D:\thuydo\upwork\xarray-spatial\xrspatial\pathfinding.py:302: Warning: Start at a non crossable pixel
    warnings.warn('Start at a non crossable pixel', Warning)

-- Docs: https://docs.pytest.org/en/latest/warnings.html
============================================================================ 83 passed, 19 warnings in 82.47s (0:01:22) ============================================================================