Adapt nitrile install scripts as a result of changes in nitrile directory structure.

What does this MR do?

Adapt the nitrile install scripts as a result of adding the nitrile global commands.

For more information, see: nitrile#26 (closed).

Changes to public APIs

Author's checklist (required)

• Intermediate commits compile (use git rebase -i main if not)
• Newly added code has a style consistent with the rest of the repository
• Newly added code is documented (guidelines)

Related issues