test: fix abstraction leakage in tests for TrafficParticipantControlUnit

CI:

link to pipeline: https://ci.eclipse.org/openpass/job/GtGenCore/view/change-requests/job/MR-152/

Functionality:

receive an osi::TrafficCommand through the osi_traffic_participant_interface, so that the openPASS Complex Controller and SCM can be simulated with ASTAS.

current Mock for ITrafficParticipantModel in master branch is a TpmExample class in separate .so library which always import: https://gitlab.eclipse.org/eclipse/openpass/gt-gen-core/-/blob/main/Core/Environment/Controller/Internal/ControlUnits/BUILD.bazel?ref_type=heads#L366

Issue 1: behavior of TpmExample cannot be tuned in tests and doesn't allow inspect calling arguments.

Issue 2: unit tests shouldn't be depend on any external library and global configs. This should be tested in separate integration test.

More concrete expectations what shall be done

• Remove unit tests dependency on external library
• Write separate unit test, which check validity of searching external library path
• Write separate integration test, which check validity of importing external .so library