Pinned pages order is not kept after publishing a space

When publishing only a space, the pinned pages order is not preserved, even though the "Publish page order" flag is set to "Yes". This issue only happens for spaces in the book, but it works correctly (the pinned order is preserved) when publishing the whole book.

To reproduce:
1. set up a space and arrange the pages in some order using the pinned pages functionality. This will change the order of the pages.
2. Publish the space with the "Publish page order" set to "Yes"

Expected result:
The published space has the same page order which was set using the pinned pages functionality.

Actual result:
The published space does not display the pages in the order they were pinned, but in alphabetical order.

This issue does not happen when publishing the whole book.
Tested on Book Versions 1.26 and XWiki 16.4.6