Update and refactor Python files

[gz83]

1. Reformatted Python code using Microsoft's official VS Code extension Black Formatter.

https://github.com/microsoft/vscode-black-formatter

2. Fixed an issue in setup.py where PGO files were not downloaded when no arguments were passed (i.e., when building the AVX version).

3. clean.py now better identifies and cleans up PGO files and output directories after compilation.

4. make_portable_win.py now supports copying the installer directly from the build output directory and renaming the portable archive according to Thorium's naming convention.

[gz83]

@Alex313031

PTAL

:)