dist/tools/bmp: in-line dependencies using PEP 723

[basilfx]

Contribution description

PEP 723 is an accepted proposal to in-line script metadata. One such use cases is to list script dependencies inside the script, which makes the requirements.txt redundant.

With the correct shebang, it becomes even possible to run the script directly, without creating a virtual environment and installing dependencies in advance. Combining both makes the execution of single-file scripts within RIOT much easier and friendlier.

PEP 723 metadata can be used by pipx and can be easily installed when pip is available. It is maintained by the PyPA, just like pip.

I chose this file to start with, but there are at least five more scripts with requirements.txt that could benefit from the same change. Because pip install still requires a requirements.txt file, which is generally accepted during development, I kept both for now. Aan open issue exists to add support for reading dependencies from PEP 723, which might make it superfluous in the future.

Testing procedure

Ensure that pipx is installed.

Alternatively, execute it from the dist/tools/bmp folder.

This script is part of the Black Magic Debugger. Execute it from the dist/tools/bmp folder, or compile any application and use PROGRAMMER=bmp to execute it from the build process.

Issues/PRs references

None

[mguetschow]

While I like the idea of getting rid of separate requirements.txt files and legacy pip, it's a bit unfortunate that the dependency information is now doubled in both files. I think you should add least add a comment on both sites that they need to be kept in sync.