Fix argument passing to qc wf in rna_singlesample

[rcannood]

Changelog

• workflows/rna/rna_singlesample: Fix argument passing to the qc subworkflow.

Issue ticket number and link

Closes #xxxx (Replace xxxx with the GitHub issue number)

Checklist before requesting a review

• [x] I have performed a self-review of my code

• [x] Conforms to the Contributor's guide

• Check the correct box. Does this PR contain:

  • [ ] Breaking changes
  • [ ] New functionality
  • [ ] Major changes
  • [ ] Minor changes
  • [ ] Documentation
  • [x] Bug fixes

• [x] Proposed changes are described in the CHANGELOG.md

• [x] CI tests succeed!