chore: use if TYPE_CHECKING: blocks (#2866)

unit_test/main_tests/conftest.py

@@ -1,8 +1,9 @@
+from __future__ import annotations
+
 import contextlib
 import platform as platform_module
 import subprocess
 import sys
-from collections.abc import Generator, Iterator
 from pathlib import Path
 from typing import Any
 
@@ -13,6 +14,10 @@ from cibuildwheel.logger import Logger
 from cibuildwheel.platforms import android, ios, linux, macos, pyodide, windows
 from cibuildwheel.util import file
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Generator, Iterator
+
 
 class ArgsInterceptor:
     def __init__(self) -> None: