fix: do not pre-seed setuptools / wheel in virtual environment (#1819)

test/test_abi_variants.py

@@ -4,6 +4,12 @@ import textwrap
 
 from . import test_projects, utils
 
+pyproject_toml = r"""
+[build-system]
+requires = ["setuptools", "wheel"]
+build-backend = "setuptools.build_meta"
+"""
+
 limited_api_project = test_projects.new_c_project(
     setup_py_add=textwrap.dedent(
         r"""
@@ -30,6 +36,8 @@ limited_api_project = test_projects.new_c_project(
     setup_py_setup_args_add="cmdclass=cmdclass",
 )
 
+limited_api_project.files["pyproject.toml"] = pyproject_toml
+
 
 def test_abi3(tmp_path):
     project_dir = tmp_path / "project"
@@ -155,6 +163,8 @@ ctypes_project.files["test/add_test.py"] = textwrap.dedent(
     """
 )
 
+ctypes_project.files["pyproject.toml"] = pyproject_toml
+
 
 def test_abi_none(tmp_path, capfd):
     project_dir = tmp_path / "project"