Bug report

Assign parameter to any node doesn't work, if the node has namespace.

Required Info:

• Operating System:
  • ubuntu:20.04
• Installation type:
  • binaries
• Version or commit hash:
  • ros-galactic
• DDS implementation:
  • Fast-RTPS
• Client library (if applicable):
  • rclcpp

Steps to reproduce issue

install demo_nodes with apt install ros-galactic-demo-nodes-cpp
create config.yaml file with the following content

/*:
  parameter_blackboard:
    ros__parameters:
      miau: "miau_config"

run /opt/ros/galactic/lib/demo_nodes_cpp/parameter_blackboard --ros-args -r __ns:=/aaaa --params-file config.yaml
run ros2 param list

Expected behavior

ros2 param list should list the parameter miau, expected output is

/aaaa/parameter_blackboard:
  miau
  qos_overrides./parameter_events.publisher.depth
  qos_overrides./parameter_events.publisher.durability
  qos_overrides./parameter_events.publisher.history
  qos_overrides./parameter_events.publisher.reliability
  use_sim_time

Actual behavior

miau parameter isn't added to the node, ros2 param list returns

/aaaa/parameter_blackboard:
  qos_overrides./parameter_events.publisher.depth
  qos_overrides./parameter_events.publisher.durability
  qos_overrides./parameter_events.publisher.history
  qos_overrides./parameter_events.publisher.reliability
  use_sim_time