camel-salesforce: allow to retrieve CDC json schema from meta service

To get the full schema of a change event message, it it possible to make a GET request to the REST API that includes the schema ID sent in the event message, as example:

/vXX.X/event/eventSchema/<Schema_ID>

or by using the event name:

/vXX.X/sobjects/<EventName>/eventSchema

It would be nice if the meta data extension would be able to return the json schema of the