rptest: run rpk tests against redpanda cloud

[andrewhsu]

Updates to the redpanda ducktape test helpers RpkTool and RpkConsumer so they can connect to redpanda cloud. This enables RpkToolTest, which does various topic operations, to be able to test redpanda cloud.

Fixes https://github.com/redpanda-data/cloudv2/issues/7909

Output of manual test run against redpanda cloud:

bash$ ducktape --debug --globals=/home/ubuntu/redpanda/tests/globals.json --cluster=ducktape.cluster.json.JsonCluster --cluster-file=/home/ubuntu/redpanda/tests/cluster.json --test-runner-timeout=3600000 tests/rptest/tests/rpk_topic_test.py::RpkToolTest
...
test_id:    rptest.tests.rpk_topic_test.RpkToolTest.test_consume_as_group
status:     PASS
run time:   25.118 seconds
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_id:    rptest.tests.rpk_topic_test.RpkToolTest.test_consume_from_partition
status:     PASS
run time:   16.124 seconds
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_id:    rptest.tests.rpk_topic_test.RpkToolTest.test_consume_newest
status:     PASS
run time:   37.517 seconds
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_id:    rptest.tests.rpk_topic_test.RpkToolTest.test_consume_oldest
status:     PASS
run time:   56.293 seconds
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_id:    rptest.tests.rpk_topic_test.RpkToolTest.test_produce
status:     PASS
run time:   37.001 seconds
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_id:    rptest.tests.rpk_topic_test.RpkToolTest.test_create_topic
status:     PASS
run time:   6.571 seconds
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_id:    rptest.tests.rpk_topic_test.RpkToolTest.test_add_unfeasible_number_of_partitions
status:     PASS
run time:   6.435 seconds
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_id:    rptest.tests.rpk_topic_test.RpkToolTest.test_create_topic_with_invalid_config.config_type=cleanup.policy
status:     PASS
run time:   5.953 seconds
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_id:    rptest.tests.rpk_topic_test.RpkToolTest.test_create_topic_with_invalid_config.config_type=compaction.strategy
status:     PASS
run time:   5.781 seconds
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_id:    rptest.tests.rpk_topic_test.RpkToolTest.test_create_topic_with_invalid_config.config_type=compression.type
status:     PASS
run time:   6.187 seconds
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_id:    rptest.tests.rpk_topic_test.RpkToolTest.test_create_topic_with_invalid_config.config_type=message.timestamp.type
status:     PASS
run time:   5.920 seconds 
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
============================================================================================================================================================================================================================
SESSION REPORT (ALL TESTS)
ducktape version: 0.8.8   
session_id:       2023-08-04--011
run time:         3 minutes 29.055 seconds
tests run:        11
passed:           11
failed:           0
ignored:          0
opassed:          0
ofailed:          0
============================================================================================================================================================================================================================

Backports Required

• none - not a bug fix
• none - this is a backport
• none - issue does not exist in previous branches
• none - papercut/not impactful enough to backport
• v23.2.x
• v23.1.x
• v22.3.x

Release Notes

• none

[andrewhsu]

/ci-repeat 1
skip-units
tests/rptest/tests/rpk_topic_test.py::RpkToolTest.test_create_topic

[andrewhsu]

unrelated unit test failure and all ducktape tests pass. this PR is ready for review.

[savex]

Build fails seems unrelated to current changes