None type non explicitly accepted for samples in RunModel

[Migoyan]

Describe the bug
beartype violation error raised (not list or numpy array) when passing None value to samples parameter of RunModel class.
This behaviour is inconsistent with the default value, and with the documentation where None is an accepted value for samples.

To Reproduce
Create a RunModel such as RunModel(..., samples=None)

Expected behavior
No error

Desktop (please complete the following information):

• OS: ubuntu 22
• version: 4.1.6