chore: use if TYPE_CHECKING: blocks (#2866)

test/test_cpp_standards.py

@@ -1,10 +1,14 @@
-from pathlib import Path
+from __future__ import annotations
 
 import jinja2
 
 from . import utils
 from .test_projects import TestProject
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from pathlib import Path
+
 cpp_test_project = TestProject()
 
 setup_py_template = r"""