chore: refactor cibuildwheel.utils (#2252)

* chore: refactor cibuildwheel.utils

* rework build_frontend extra flags

* ci(fix): use tonistiigi/binfmt:qemu-v8.1.5 image for qemu

test/conftest.py

@@ -8,8 +8,9 @@ import pytest
 from filelock import FileLock
 
 from cibuildwheel.architecture import Architecture
+from cibuildwheel.ci import detect_ci_provider
 from cibuildwheel.options import CommandLineArguments, Options
-from cibuildwheel.util import detect_ci_provider, find_uv
+from cibuildwheel.venv import find_uv
 
 from .utils import EMULATED_ARCHS, platform