Proposal: Use PlatformIO Python in colcon build

[maru-n]

Regarding the execution of 'colcon build' within library_builder.py:

In my local environment, the 'cmake' command within 'colcon build' in library_builder.py seems to find and use the system's Python instead of the Python version bundled with PlatformIO. Consequently, if I use a virtual environment like pyenv, 'colcon build' fails.

I can make PlatformIO use its bundled Python version by setting the -DPython3_EXECUTABLE option in --cmake-args.

This appears to be the desired behavior, for the following reasons:

1. extra_script.py installs required packages such as 'colcon' into PlatformIO's environment.
2. The PlatformIO environment is activated prior to executing the 'colcon build' command.

In fact, setting this option allows all builds to be completed using PlatformIO's Python version, which works well in a pyenv environment.

However, I believe that executing the build on a system with ROS already installed is also a correct approach.

While I'm not fully versed in this library to make a definitive call, I thought it pertinent to raise this issue and have therefore submitted this PR.

[normen]

Would be great if this was merged as the computer I am building the micro-ros part is not the one running ros2