GlassBlur and GridDropout fail test_augmentations_serialization_with_custom_parameters

[Dipet]

Example parameters:

[A.GlassBlur, dict(sigma=0.8, max_delta=5, iterations=3, mode="exact")],
[
    A.GridDropout,
    dict(
        ratio=0.75,
        unit_size_min=2,
        unit_size_max=10,
        shift_x=10,
        shift_y=20,
        random_offset=True,
        fill_value=10,
        mask_fill_value=20,
    ),
],

[ternaus]

Cannot reproduce.

Added checks to tests in #1571