Import does not update the url alias if the content already exists.

Problem/Motivation

When importing a content, the url alias does not get updated if the content already exists.

Steps to reproduce

Create a content in the source (siteA) without url alias
export it and import to another siteB
update the same content on the source (siteA) with the url alias
re-export and import to siteB
The content does not get updated with the URL alias.

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes