Issue Description: 

Current error handling strategies in RHOSE are push based: users can configure a webhook or a Kafka topic (RHOSAK) where to send errors. This helps to have full control of data retention but it requires users to provide a “resource” that RHOSE can use.

There are use cases where this is not possible (e.g not possible to expose on the customer side an endpoint over the internet) and this makes a more complicated “getting started” experience because RHOSE requires additional external dependencies for a customer to see errors in processing.

It should be useful to have an option (poll based) where it is possible for the user to invoke an endpoint and get errors in their Event processing. This requirement has been raised by Heiko Rupp for Notification Service use case but it is quite generic.

Acceptance Criteria:

• Users should be able to configure poll based error strategy and get an endpoint to use to fetch the last 'N' errors that were sent to the DLQ for their Bridge.

Additional Information:

• https://docs.google.com/document/d/1alJjHlsYXLYGuTUD1YX25rWiEUlFYWuO8Bix3Rc-l3I/edit?usp=sharing