Chore - Refactor integration test to be configurable

[hhandoko]

Context

Currently the integration test is hardcoded to use embedded Cassandra running at port 9147. A simple refactoring will enable the tests to run against standalone Cassandra instances.

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## Definition of Done

Integration test should accept system properties to override the default parameters (much like the command-line / standalone JAR parameters), for example:

mvn integration-test -Dcassandra.migration.keyspace.name=cassandra_migration_test