Setting `deleteRecursive` to false results in KIO's `DeleteJob` listing the
target folder first and deleting the children entries one by one
(see documentation of `KProtocolManager::canDeleteRecursive()`).

This was causing all files to be trashed when deleting an account folder
from the root gdrive:// url. Now the account folder will be just deleted
from the list of account, without touching the account files.

Task: T3987
CCMAIL: aacid@kde.org