Nl nl ssn issue #2253

[Dutcho]

What does this change

Fix issue #2253 on ssn() in 'nl_NL' provider.

What was wrong

Generated ssn() values had unique leading 8 digits, which is not a BSN (Dutch ssn) requirement. As a consequence the range (number of possible values) was limited to 10! / 2! * 9 / 10.

How this fixes it

Replace random.sample() by random.choices() and continue in case digits[:2] == [0, 0] in ssn() code. Now the range is 10 ** 8 * 99 / 100 * 9 / 10, and I generated 20 million unique BSN's without issue (other than 2.6 million collisions).

Checklist

• [X] I have read the documentation about CONTRIBUTING
• [X] I have read the documentation about Coding style
• [ ] I have run make lint (I didn't install locally)