site_factory: Fix ibexadesign config

[adriendupuis]

Question	Answer
JIRA Ticket	N/A
Versions	5.0, 4.6
Edition	Experience, Commerce

ezdesign defines templates for your sites, so add them before continuing.
Next, add the configuration for ezdesign on the same level as ezplatform:

The original sentence was about this old example:

ezplatform:
    siteaccess: …
ezdesign:
    design_list: …

Fix previous rebranding update to avoid confusion between the design path @ezdesign→@ibexadesign and the design conf ezdesign.design_list→ibexa_design_engine.design_list

ibexa:
    siteaccess: …
ibexa_design_engine:
    design_list: …

I guess the reader can indent this correctly without the instruction about levels. A link to design engine doc page could help readers not aware enough about this part.

Preview: https://ez-systems-developer-documentation--2998.com.readthedocs.build/en/2998/multisite/site_factory/site_factory/#enable-site-factory

Checklist

• Text renders correctly
• Text has been checked with vale
• Description metadata is up to date
• Redirects cover removed/moved pages
• Code samples are working
• PHP code samples have been fixed with PHP CS fixer
• Added link to this PR in relevant JIRA ticket or code PR

[github-actions]

Preview of modified files

Preview of modified Markdown:

• docs/multisite/site_factory/site_factory.md

[dabrt]

The original description was confusing and inconsistent in terms of terminology. The change clears out a lot!