[Build] make sure the custom msg is built into header file

[DeboBurro]

Summary

1. Fix the case that CustomMsg.h is not found because the CMakeLists.txt doesn't wait till all custom messages are built into header files.

Errors     << livox_laser_simulation:make /root/catkin_ws/logs/livox_laser_simulation/build.make.000.log                                                                              
/root/catkin_ws/src/..../Mid360_simulation_plugin/livox_laser_simulation/src/livox_points_plugin.cpp:18:10: fatal error: livox_laser_simulation/CustomMsg.h: No such file or directory
   18 | #include <livox_laser_simulation/CustomMsg.h>