[mock goal] coverage report should be generated on demand

[redfish4ktc]

Currently, the report is accurate only if the goal is in pause to let the mock runner registers all mock requests. When the noBlock parameter is set to true, the runner ends and perform the generation. As the mock services are still available (the jetty server is still running), we can run tests against the mock, but the coverage report will never be updated.

As we inject the coverage builder by ourself in the mock runner, we should find a way to keep reference to the builder and force the generation afterwards (maybe by creating a new goal and disabling coverage report generation at the end of the mock runner execution)

[redfish4ktc]

1st poc is available in the feature-119-mock_goal-coverage-report-generation-later branch