feat(LAB-465): Allow custom type for Cloud Events

Allow custom type for Cloud Events

Description:

So far Cloud Event Service was expecting Compliance Credentials only. We want to open it to other Cloud Event types.

Solution:

• POST : Do not enforce event and credential types
• GET : Add an optional type query parameter

If the Cloud Event has a eu.gaia-x.credential type, all credential subjects must have gx:compliance type. Otherwise any kind of credential subject type can be used.

Fixes:

LAB-465