Hide drop zone for read-only users

Steps to reproduce:

1. create a user whose name is "reader"
2. as an administrator, create a File document with no attached file
3. as an administrator, grant the Read permission to "reader" on this document
4. as "reader", navigate to this document
5. try to drop a file in the D&D area

Observe that the upload of the file never ends. If you look at the Network traces, you'll see an exception for the corresponding upload request

{"entity-type":"exception","status":403,"message":"Privilege 'WriteProperties' is not granted to 'reader'"}

Expected behavior: the D&D zone should not be displayed for a read only user.

Note that the refactoring done by NXP-24084 has fixed this problem for Nuxeo 10.1 and above