Map parallel http calls automatically

**User story**
As a citrus test developer, I want parallel http send actions to be mapped automatically to their receive actions so that I don't have to map them manually.

**Additional context**
As https://github.com/citrusframework/citrus/issues/458 has shown, it's currently required to map parallel http requests manual by their `citrus_message_id`. This is a recurring manual mapping that should be resolved by the framework.