fix: add throw exception for rsa salt

[vincentandreas]

What?

Implement throw exception in RSA PSS, when given salt length = 0, in Sign / Verify function

Why?

It improves UX and makes implementation predictable.

Checklist

• I have performed a self-review of my code.
• I have commented on my code, particularly in hard-to-understand areas.
• I have added tests for my changes.
• I have run linter and tests locally (make check) and all pass.

Checklist: Documentation (only for k6 maintainers and if relevant)

Please do not merge this PR until the following items are filled out.

• I have added the correct milestone and labels to the PR.
• I have updated the release notes: link
• I have updated or added an issue to the k6-documentation: grafana/k6-docs#NUMBER if applicable
• I have updated or added an issue to the TypeScript definitions: grafana/k6-DefinitelyTyped#NUMBER if applicable

Related PR(s)/Issue(s)

Issues #4265
Previous PR #4659

[AgnesToulet]

Hi! Sorry for the delay and thanks a lot for your contribution!

This looks good (just left some wording suggestions) and works great but we probably want to update the tests in this case to expect the error, could you update your PR with updated tests please?

[vincentandreas]

hi @AgnesToulet , thankyou for the feedback! I'll add that later.

[vincentandreas]

hi @AgnesToulet could you elaborate, which file that contain test that need to be updated?