Controller manager name matches container name in composable nodes

[Tacha-S]

As mentioned in this comment,
when launching gz_server with composable nodes, the node options passed to the controller manager include the container's name or namespace.

This results in the controller manager forcibly inheriting the same name as the container node.

gz_ros2_control/gz_ros2_control/src/gz_ros2_control_plugin.cpp

Lines 441 to 446 in 07a2d3b

	this->dataPtr->controller_manager_.reset(
	new controller_manager::ControllerManager(
	std::move(resource_manager_),
	this->dataPtr->executor_,
	controllerManagerNodeName,
	this->dataPtr->node_->get_namespace(), options));