docs: updated method of setting hidden views, deprecated old option

[jacalata]

#617

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. If this is still relevant, please comment to keep it open.

[jacalata]

Closing — the docs situation this was tracking is resolved:

• The hidden_views parameter was removed from publish() in Development to master for v0.12 #646 (v0.12), so there's nothing left to mark as deprecated.
• The WorkbookItem.hidden_views attribute is documented in the class docstring (added in docs: workbook docstrings #1488).