Web API: inconsistencies on api-key resource

[mguidon]

Is there an existing issue for this?

• I have searched the existing issues

Which deploy/s?

other (e.g. local)

Current Behavior

1. Code is required but does no make sense
   

2. Expiration seems useless here:

Expected Behavior

No response

Steps To Reproduce

No response

Anything else?

No response

### Event Horizon

[pcrespov]

• @GitHK already solved 1 in ✨oSPARC API keys are created and removed if a service requires them #5004
• Related with Extend webserver's ApiKey API #5022

[pcrespov]

• review API in comparison with e.g. folders resources
• fix delete
• update response and request body with proper models.

[giancarloromeo]

Solved in #6843