Using `axes_sums_subject_to` on a `BinaryVariable` with size 0 results in a crash when initializing a state

[wbernoudy]

In [1]: from dwave.optimization import Model

In [2]: model = Model()

In [3]: b = model.binary(shape=0, axes_sums_subject_to=[(0, ">=", 1)])

In [4]: model.lock()
Out[4]: <contextlib._GeneratorContextManager at 0x7ffff13952b0>

In [5]: model.states.resize(1)

In [6]: b.state(0)
zsh: floating point exception (core dumped)  ipython