IBX-3966: Used user_content_type_identifier configuration key inside user service

[ViniTou]

Question	Answer
JIRA issue	IBX-3966
Type	improvement
Target Ibexa version	v4.3
BC breaks	yes/no

Not sure how we should handle BC in that case. Overriding userClassID was hard and as I am aware totally not documented. On the same way, just doing that without changing the adminUI parameter also did nothing in terms of using different CT than the default one.

Checklist:

• Provided PR description.
• Tested the solution manually.
• Provided automated test coverage.
• Checked that target branch is set correctly (main for features, the oldest supported for bugs).
• Ran PHP CS Fixer for new PHP code (use $ composer fix-cs).
• Asked for a review (ping @ibexa/engineering).

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
4 Code Smells

No Coverage information
0.0% Duplication

[alongosz]

I wonder if this should be a Repository setting, not SiteAccess. How would system behave if for admin you would have one identifier and for site other one? Not that we practiced this till now, but maybe it's a good moment to distinguish these settings.
Perhaps something we can discuss internally later today?

[ViniTou]

@alongosz
As discussed, I had moved resolving configuration into user service itself.

[tomaszszopinski]

QA approved on IbexaDXP 4.3 commerce.