Address deprecation warnings in tests

[Mohamed-Waiel-Shikfa]

It would be nice to address the following deprecation warnings in tests:

C:\projects\cpython-cmu-graphics-0l7rb\tests\test_image_gen.py:49: DeprecationWarning: Starting with ImageIO v3 the behavior of this function will switch to that of iio.v3.imread. To keep the current behavior (and make this warning disappear) use import imageio.v2 as imageio or call imageio.v2.imread directly.
image_1_data = imageio.imread(path_1)
C:\projects\cpython-cmu-graphics-0l7rb\tests\test_image_gen.py:54: DeprecationWarning: Starting with ImageIO v3 the behavior of this function will switch to that of iio.v3.imread. To keep the current behavior (and make this warning disappear) use import imageio.v2 as imageio or call imageio.v2.imread directly.
image_2_data = imageio.imread(path_2)
Command exited with code -1

Not extremely important but it's one of those small quality of life thing.
I am not sure if we want the current behavior or the other one, maybe one of the main maintainers could fix this.

[schmave]

Agreed, this would be nice to fix!