Standardize the inconsistent logging, asserting, and println approach in JLM system tests

[Mesbah-Alam]

The reporting and error logging approach in JLM tests is inconsistent. Some of the tests generate "CSV" data files where some info is logged. The rest go into standard err and out. There are also some tests (e.g. VMLogger, where a log file is used to log detailed results of what the invoked Bean API's return. The output handling is not standardized in general.

This issue will track the work of standardizing the inconsistent logging, asserting, and println approach in JLM system tests