Add seed into traffic_swarm_parameters

@arauschert requested to forward random_seed into gtgen::core::environment::traffic_swarm::TrafficSwarmXosc without adding new parameter into constructor, but use TrafficSwarmParameters instead.

TrafficSwarmXosc already use mantle_api::TrafficSwarmParameters as parameters.

Theoretically it possible to add seed into mantle_api::TrafficSwarmParameters. [ MR in mantle-api repo with adding: eclipse/openpass/mantle-api!168 (closed) ]

However there is already usage in repo openscenario1_engine. https://gitlab.eclipse.org/eclipse/openpass/openscenario1_engine/-/blob/main/engine/src/Storyboard/GenericAction/TrafficSwarmAction_impl.cpp?ref_type=heads#L68

it is still possible to:

• forward seed into OpenScenarioEngine::v1_2::TrafficSwarmAction
• or modify mantle_api::TrafficSwarmParameters directly in GtGenEnvironment::InitTrafficSwarmService

However in my opinion it much better and easier to use gtgen::TrafficSwarmParameters instead of mantle_api::TrafficSwarmParameters