Describe the bug
After call to notch_approximation_law.stress(value), the value object is sometimes changed. This is an unwanted side effect of this function.

To Reproduce
Hard to reproduce, it was observed in _compute_hcm_RAM where we have:

extended_neuber = pylife.materiallaws.notch_approximation_law.ExtendedNeuber(E, K_prime, n_prime, K_p)
extended_neuber_binned = pylife.materiallaws.notch_approximation_law.Binned(
        extended_neuber, maximum_absolute_load, 100)

This calls materiallaws.notch_approximation_law.Binned._create_bins_single_assessment_point where self._lut_primary_branch.load is changed during

self._lut_primary_branch.stress \
            = self._notch_approximation_law.stress(self._lut_primary_branch.load)

Expected result
self._notch_approximation_law.stress does not change the argument, self._lut_primary_branch.load in this case.

Environment (please complete the following information):

• OS: Windows 11
• How installed: pip
• Version: develop branch

Additional context
The problem was tracked back and it seems scipy.optimize.newton(func, x0) changes x0 if it is an object like a pd.Series.