[core] [Slice] Error when end attribute is out of bound

In current implmentation of Slice if end attribute is out of bound the following error is raised:

Slice_Op: ROI (9223372036854775808) of Slice operator out of bounds (1) on axis 0, with (Start, End, Step) = (0, 9223372036854775807, 1)

However, ONNX standard defines that an outbound value means max.

This issue affect aidge_core (forward dims) and aidge_backend_cpu (forward)