Fix outside-of-project check when project path is not canonical.
Description
Fix outside-of-project check when project path is not canonical.
The issue happens on Silverblue where /home is a symlink to /var/home. With this element-path is something like /var/home/user/project/elements, when the project path is /home/usr/project.
Comparing canonical paths solves the issue.
This merge request, when approved, will close issue/bug: Fixes #673 (closed).