[improve][ci] Add new CI unit test group "Broker Group 4" with cluster migration tests

[lhotari]

Motivation

There are too many tests in the "broker" TestNG test group which gets executed in the "Broker Group 1" CI job.
The tests could take over 60 minutes to run and that is currently the timeout.

Modifications

Add a new "Broker Group 4" unit test group and build job.
Move one of the slowest tests "ClusterMigrationTest" to "cluster-migration" TestNG test group. Assign "cluster-migration" to "Broker Group 4".

Documentation

• doc
• doc-required
• doc-not-needed
• doc-complete

[lhotari]

@rdhabalia @vineeth1995 @vraulji567 Please review!

I'm moving ClusterMigrationTest since it seems to be one of the slowest tests.

Gradle Enterprise analytics from a few days ago:
https://ge.apache.org/s/ucnihfo5rnoyi/tests/slowest-tests
https://ge.apache.org/s/ucnihfo5rnoyi/tests/goal/org.apache.pulsar:pulsar-broker:surefire:test@default-test/details/org.apache.pulsar.broker.service.ClusterMigrationTest?top-execution=1

Links to Gradle Enterprise build scans can be found in the scheduled master branch builds:
https://github.com/apache/pulsar/actions/workflows/pulsar-ci.yaml?query=branch%3Amaster

Scroll to the summary of the build job in the summary view
example:

online:
https://github.com/apache/pulsar/actions/runs/6533326173/attempts/1#summary-17738916032

[lhotari]

/pulsarbot rerun-failure-checks

[mattisonchao]

I am unsure if we should start a discussion or notification for the community. :)

[lhotari]

I am unsure if we should start a discussion or notification for the community. :)

@mattisonchao I have sent a notification on the dev mailing list, it's https://lists.apache.org/thread/s7odd1kh5mwgvmcdf2ynkfbh68zbcomf .

[tisonkun]

Give it a try.