Feature: Is UPB (unextendible product basis)

[vprusso]

Given a collection of vectors, determine if the set constitutes an unextendible product basis (UPB).

According to arXiv:quant-ph/9808030:

An unextendible product basis (UPB) for a multipartite quantum system is an incomplete orthogonal product basis whose complementary subspace contains no product state.

In spirit, the functionality of being able to determine whether a collection of vectors form a UPB can be derived from the QETLAB package, specifically the function "IsUPB".

The functionality for this should be created in state_props/is_unextendible_product_basis.py with corresponding unit tests found in tests/test_state_props/test_is_unextendible_product_basis.py. Be sure to also update the docs in /docs/states.rst under "Properties of Quantum States" with toqito.state_props.is_unextendible_product_basis.py.

Please ensure proper credit is provided to QETLAB as serving as the inspiration for including this function.