feat: stricter selector parsing, refactor to platforms module (#2291)

* feat: stricter selector parsing, refactor to `platforms` module

- Use a different method to build nothing
- Make the check aware of enable groups

* optimise unit tests - a specific platform module API for all configs

Unit test time: 26.2s -> 13.1s

* Remove unnecessary get_platform_module function

unit_test/main_tests/conftest.py

@@ -6,7 +6,8 @@ from pathlib import Path
 
 import pytest
 
-from cibuildwheel import __main__, architecture, linux, macos, pyodide, windows
+from cibuildwheel import __main__, architecture
+from cibuildwheel.platforms import linux, macos, pyodide, windows
 from cibuildwheel.util import file