Default retry and dlq topic name fixed as per the doc

[ngoyal16]

Motivation

In Apache pulsar documention default retry and dlq topic names are as follows

for Retry: <topicname>-<subscriptionname>-RETRY
https://pulsar.apache.org/docs/2.10.x/concepts-messaging#retry-letter-topic
for DLQ: <topicname>-<subscriptionname>-DLQ
https://pulsar.apache.org/docs/2.10.x/concepts-messaging#dead-letter-topic

Modifications

added topicname also in the default Retry and DLQ topic name

Verifying this change

• Make sure that the change passes the CI checks.

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This change is a trivial rework / code cleanup without any test coverage.

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• Added integration tests for end-to-end deployment with large payloads (10MB)
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[ngoyal16]

@nodece how retry mechnism works for partition topics

does it create seprate retry topic for each partitions? same applies to dlq?

[nodece]

@nodece how retry mechnism works for partition topics

does it create seprate retry topic for each partitions? same applies to dlq?

I think it's the same, it should be based on the namespace with the subscription name.

[ngoyal16]

@RobertIndie or @nodece any idea when this can be merged

[nodece]

@ngoyal16 Could you rebase your code?

[ngoyal16]

@nodece rebase done