datasource-rootPath is ignored when saving data.

Steps to reproduce:

1. (using datasource example in documentation)
2. include rootPath in datasource:

   datasource:
     workspace: tourguides
     rootPath: /tours
     namespaces:
       mt: https://www.magnolia-travel.com/jcr/1.0/mt
     autoCreate: true
   
   model:
     nodeType: mt:tourGuide
     properties:
       - name: birthday
         type: Date
       - name: gender
       - name: shortBio
   

1. Open tourGuide app
2. Create a new tour and save it

Current result

The new tour is not displayed in the browser view, since it is taking into consideration /rootPath (see MGNLUI-6129). If you use the JCR Browser app to see the tourguides workspace, you will see that the tour was included in root (//) instead of taking into consideration rootPath (/tours)

Expected result

The new tour should have been stored in rootPath instead of root.

NOTES:
When the app is opened an error comes up if there is path tours does not exist in advance.
When validating the tour name, it is taking into consideration root instead of rootPath