Do not rely on kpoints validation from aiida-quantumespresso

[greschd]

The code below relies on the PwBaseWorkChain input validation to catch that either kpoints or kpoint_distance needs to be set:

aiida-wannier90-workflows/aiida_wannier90_workflows/workflows/wannier.py

Lines 361 to 370 in 18ad0e0

	try:
	inputs.kpoints
	except AttributeError:
	# then kpoints_distance must exists, since this is ensured by inputs check of this workchain
	from aiida_quantumespresso.workflows.functions.create_kpoints_from_distance import create_kpoints_from_distance
	force_parity = inputs.get('kpoints_force_parity', orm.Bool(False))
	kmesh = create_kpoints_from_distance(
	self.ctx.current_structure, inputs.kpoints_distance,
	force_parity
	)

However (maybe since a recent release?) aiida-quantumespresso doesn't do that, instead the k-points are checked after the workchain has started, and an error code is returned if they are invalid.

This means that this workchain will except when both kpoints and kpoint_distance or not set, instead of giving a "well-behaved" error.