Non-orthogonal slabs break shrikwrap

[efako]

_get_starting_grid(atoms, 1)

returns None none.
consequence:

shrinkwrap_surface(atoms)
error:

ValueError                                Traceback (most recent call last)
Cell In[40], line 1
----> 1 shrinkwrap_surface(atoms)

File [/media/djrm/data1/venv/mace_paper_rev/lib/python3.12/site-packages/autoadsorbate/Surf.py:291](http://localhost:8889/media/djrm/data1/venv/mace_paper_rev/lib/python3.12/site-packages/autoadsorbate/Surf.py#line=290), in shrinkwrap_surface(slab, precision, touch_sphere_size)
    288 grid_positions = get_shrinkwrap_grid(slab, precision, touch_sphere_size=touch_sphere_size-0.2).positions
    289 slab_positions = slab.positions
--> 291 distances_to_grid = cdist(slab_positions, grid_positions).min(axis=1)
    292 mask = distances_to_grid < touch_sphere_size
    294 surf_indices = np.where(mask)[0]

File [/media/djrm/data1/venv/mace_paper_rev/lib/python3.12/site-packages/numpy/core/_methods.py:45](http://localhost:8889/media/djrm/data1/venv/mace_paper_rev/lib/python3.12/site-packages/numpy/core/_methods.py#line=44), in _amin(a, axis, out, keepdims, initial, where)
     43 def _amin(a, axis=None, out=None, keepdims=False,
     44           initial=_NoValue, where=True):
---> 45     return umr_minimum(a, axis, None, out, keepdims, initial, where)

ValueError: zero-size array to reduction operation minimum which has no identity