Explicitly state which planning pipelines to use in demo launch

[stephanie-eng]

Description

The launch file included with the Quickstart in RViz tutorial uses MoveItConfigsUtils with the panda config files in moveit_resources. By default, MoveItConfigsUtils looks for all _planning.yaml files, which picks up lerp_planning.yaml and trajopt_planning.yaml. These files produce the following errors (some logs removed for brevity):

[ERROR] [1664267382.867870261] [moveit.ros_planning.planning_pipeline]: Exception while loading planner 'lerp_interface/LERPPlanner': According to the loaded plugin descriptions the class lerp_interface/LERPPlanner with base class type planning_interface::PlannerManager does not exist. Declared types are  chomp_interface/CHOMPPlanner ompl_interface/OMPLPlanner pilz_industrial_motion_planner/CommandPlannerAvailable plugins: chomp_interface/CHOMPPlanner, ompl_interface/OMPLPlanner, pilz_industrial_motion_planner/CommandPlanner
[ERROR] [1664267382.877819227] [moveit.ros_planning_interface.moveit_cpp]: Failed to initialize planning pipeline 'lerp'.
[ERROR] [1664267383.031895256] [moveit.ros_planning.planning_pipeline]: Exception while loading planner 'trajopt_interface/TrajOptPlanner': According to the loaded plugin descriptions the class trajopt_interface/TrajOptPlanner with base class type planning_interface::PlannerManager does not exist. Declared types are  chomp_interface/CHOMPPlanner ompl_interface/OMPLPlanner pilz_industrial_motion_planner/CommandPlannerAvailable plugins: chomp_interface/CHOMPPlanner, ompl_interface/OMPLPlanner, pilz_industrial_motion_planner/CommandPlanner
[ERROR] [1664267383.041862939] [moveit.ros_planning_interface.moveit_cpp]: Failed to initialize planning pipeline 'trajopt'.

This PR modifies the launch file to explicitly use only the specified planning pipelines (OMPL, CHOMP, and Pilz), with the intent to prevent the above errors.