cd ~/vrx_ws
colcon build --merge-install

Starting >>> vrx_gazebo
Starting >>> vrx_ros
Finished <<< vrx_gazebo [0.25s]
Starting >>> wamv_description
Finished <<< wamv_description [0.05s]
Starting >>> wamv_gazebo
Finished <<< wamv_gazebo [0.04s]
--- stderr: vrx_ros
CMake Error at CMakeLists.txt:12 (find_package):
  By not providing "Findros_gz_interfaces.cmake" in CMAKE_MODULE_PATH this
  project has asked CMake to find a package configuration file provided by
  "ros_gz_interfaces", but CMake did not find one.

  Could not find a package configuration file provided by "ros_gz_interfaces"
  with any of the following names:

    ros_gz_interfacesConfig.cmake
    ros_gz_interfaces-config.cmake

  Add the installation prefix of "ros_gz_interfaces" to CMAKE_PREFIX_PATH or
  set "ros_gz_interfaces_DIR" to a directory containing one of the above
  files.  If "ros_gz_interfaces" provides a separate development package or
  SDK, be sure it has been installed.


---
Failed   <<< vrx_ros [0.42s, exited with code 1]

Summary: 3 packages finished [0.49s]
  1 package failed: vrx_ros
  1 package had stderr output: vrx_ros
  1 package not processed