CI: adding valgrind job to Nightly

[samir-nasibli]

Description

This PR was created for initial testing with valgrind. The developments from here will be analyzed and presented for discussion for further implementation.

• [ ] I have reviewed my changes thoroughly before submitting this pull request.
• [ ] I have commented my code, particularly in hard-to-understand areas.
• [ ] I have updated the documentation to reflect the changes, if necessary (updated in # - add PR number)
• [ ] The unit tests pass successfully.
• [ ] I have run it locally and tested the changes extensively.
• [ ] I have resolved any merge conflicts that might occur with the base branch.
• [ ] Git commit message contains an appropriate signed-off-by string (see CONTRIBUTING.md for details)
• [ ] I have added a respective label(s) to PR if I have a permission for that.