Unit tests veryfying expectation for curves::nurbs::calculate_evaluated_num(). Expectation is computed from closed form expressions rather then hard coded values. Purpose for this is to make the tests easier to adjust if, for example, parameter sampling pattern is changed. It should also make them easier to read and understand. Additional purpose is to create a baseline and verify changes for #144000. Implementation is essentially examples from: https://link.springer.com/book/10.1007/978-3-642-59223-2 Pull Request: https://projects.blender.org/blender/blender/pulls/143920