Discovered while testing https://issues.ibexa.co/browse/IBX-5499

Steps to reproduce:

1. Clean installation of Ibexa DXP.
2. Update tree_root setting of site Site Access:

           site:
               languages: [eng-GB]
               content:
                   tree_root:
                       location_id: 42
   

1. Enable the Site Factory - https://doc.ibexa.co/en/4.5/multisite/site_factory/site_factory/#site-factory.
2. Create a new Site in the Site Factory, name it "Test", and use default data everywhere, as domain add your admin's domain.
3. Under the Test folder that was created in the previous step create a new Landing Page.
4. Observe a resolved Site Access.

Result:
Error 500 occurs when landing page CT creation is opened. 

NoMatchingSiteAccessFoundException 

Expected result:
The resolved Site Access should be the one created in the Site Factory.