fix: remove prefix 'rook' from 'rook_on_openstack' variable because it's added...

Version Control Information

Source branch: dsuba/fix-variable-prefix
Target branch: devel

Commits:

* fix: remove prefix 'rook' from 'rook_on_openstack' variable because it's added later by update_inventory.py

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Description

This MR changes all occurences of rook_on_openstack variable to on_openstack inside this repo.

Closes: #598 (closed)

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