Remove numpy version restriction when sklearn prerequisite has been removed

[GhislainJ]

**Note: for support questions, please use https://nextcloud.dessia.tech/call/hr9z9bif

• I'm submitting a ...

  • [ ] bug report
  • [ ] feature request

• What is the current behavior?

• If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem Avoid reference to other packages

• What is the expected behavior?

• What is the motivation / use case for changing the behavior?

• Possible fixes

• Please tell us about your environment:

  • branch:
  • commit:
  • python version: