Updating just the hidden property is impossible via the REST API

Steps to reproduce:

1. Create a (non-hidden) page
2. Execute the following JavaScript snippet in the browser's console:

   fetch(require('xwiki-meta').restURL, {
     method: 'PUT',
     headers: {
       'Content-Type': 'application/json',
       'Accept': 'application/json'
     },
     body: JSON.stringify({
       hidden: true
     })
   })
   .then(response => response.json())
   .then(json => {
     console.log('Response:', json);
   })
   .catch(error => {
     console.error('Error sending PUT request:', error);
   });
   

Expected result:

The page is now hidden and the updated page is logged.

Actual result:

The page hasn't been updated and an error "Error sending PUT request: SyntaxError: JSON.parse: unexpected end of data at line 1 column 1 of the JSON data" is logged because the response is empty (status 304 not modified). This is very related to XWIKI-22336 as while the code always applies the hidden property, it never marks the document as modified after changing it.

As a workaround, any property like the title can be specified with the same value as returned by the REST API, then the document is correctly updated.