MINOR: Stable flaky e2e test share_consumer_dlq_tiered_storage_test (WIP)

[m1a2st]

The test races against local.retention.ms=10s: the share consumer must
complete partition assignment and reject all records before the second
batch is moved to tiered storage. To avoid this, use the following
configurations:

• share.coordinator.state.topic.num.partitions=3
• group.share.heartbeat.interval.ms=1500
• group.share.min.heartbeat.interval.ms=1500

Result

====================================================================================================
test_id:
kafkatest.tests.client.share_consumer_dlq_tiered_storage_test.ShareConsumerDLQTieredStorageTest.test_tiered_topic_dlq_reject.metadata_quorum=COMBINED_KRAFT
status:     PASS
run time:   49.342 seconds
----------------------------------------------------------------------------------------------------
test_id:
kafkatest.tests.client.share_consumer_dlq_tiered_storage_test.ShareConsumerDLQTieredStorageTest.test_tiered_topic_dlq_reject.metadata_quorum=ISOLATED_KRAFT
status:     PASS
run time:   57.961 seconds
----------------------------------------------------------------------------------------------------
test_id:
kafkatest.tests.client.share_consumer_dlq_tiered_storage_test.ShareConsumerDLQTieredStorageTest.test_mixed_tiered_and_local_dlq_reject.metadata_quorum=COMBINED_KRAFT
status:     PASS
run time:   59.379 seconds
----------------------------------------------------------------------------------------------------
test_id:
kafkatest.tests.client.share_consumer_dlq_tiered_storage_test.ShareConsumerDLQTieredStorageTest.test_mixed_tiered_and_local_dlq_reject.metadata_quorum=ISOLATED_KRAFT
status:     PASS
run time:   1 minute 7.973 seconds
----------------------------------------------------------------------------------------------------