[BUG] Wrong site used in link plugin

[adrien-delhorme]

Describe the bug

When using a LinkPlugin inside a static placeholder, the wrong (django) site is used when generating the link to a page located on another (django) site.

To Reproduce
Consider a multi-site setup of django-cms: Site A and Site B.

On Site A

There is a page "Page A" site-a.com/path/to/page-a/.

On Site B

We create a LinkPlugin inside a static placeholder (or in a model's PlaceholderField like a djangocms-blog Post).
We choose "Site A > Page A" in the internal page field.
The generated link points to site-b.com/path/to/page-a/ (it does not exist).

Expected behavior
The generated link must point to site-a.com/path/to/page-a/

Desktop (please complete the following information):

• OS: OSX
• Browser: Firefox
• Version: 123.0.1

Additional context
The link is correct when I remove and cms_page is not None in this condition:

djangocms-frontend/djangocms_frontend/contrib/link/models.py

Line 70 in 7d2d682

if getattr(ref_page, "node", None) and cms_page is not None:

[fsbraun]

Going through the logic, your suggestion seems right. Thanks for pointing this out!

[fsbraun]

Fixed in #195