[cwctl] do only clean static data dir content (closes #17069762)
deleting the directory itself is useless and may be a problem in automated
deployment environments (user may not have permissions to delete or create
that directory).
Document: cubicweb-doc
Title: CubicWeb Documentation
Author: Logilab
Abstract: Some base documentation for CubicWeb users and developpers
Section: Apps/Programming
Format: HTML
Index: /usr/share/doc/python-cubicweb-documentation/html/index.html
Files: /usr/share/doc/python-cubicweb-documentation/html/*