moving the class setup function to half-fat tests, so the TEST_OUT variable is reset for the half-fat tests but not the full-fat ones when being loaded by unittest.main

changing tests to check for success via the TestResult object and changing the exit code - previously failing tests were not  being picked up by the gitlab runner

reseting the IntegrationTestUtils.TEST_OUT_PATH variable upon loading each test class, was having its value carried across from previous test runs when being run as past of a test suite

some additional comments and code-tidying