corrupt test image

[dschneiderch]

I noticed yesterday that tests/data/VIS_TV_0_z300_h1_g0_e85_v500_93054.png doesn't load or open.

Turns out it doesn't affect the tests because only the path is tested but I thought i'd mention it

def test_plantcv_get_nir_tv():
    nirpath = pcv.get_nir(TEST_DATA, TEST_VIS_TV)
    nirpath1 = os.path.join(TEST_DATA, TEST_NIR_TV)
    assert nirpath == nirpath1