Add support for use cases raising exception

[michalharakal]

This is valid code, raising expception because of size of tensor.

import torch
from  gt.core import Executable

@Executable("Small Input Size")
def use_case_5():
    x = torch.randn(1, 3, 2, 2, requires_grad=True)
    conv = torch.nn.Conv2d(3, 16, kernel_size=3, stride=1, padding=0)
    y = conv(x)  # May raise an error due to small input size
    return [x], y