Don't infer the factorization scale variation scheme

[RoyStegeman]

We should explicitly define stuff in the theorycard and otherwise raise an error (which I think we do now, but either way this function should probably go)

pineko/src/pineko/evolve.py

Lines 30 to 31 in e88a4a2

	def sv_scheme(tcard):
	"""Infere the factorization scale_variation scheme to be used from the theory card.