[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Author: pre-commit-ci[bot]

tests/tox_env/python/virtual_env/package/conftest.py

@@ -49,7 +49,7 @@ def pkg_with_pdm_backend(
 ) -> Path:
     tmp_path = tmp_path_factory.mktemp("skeleton")
 
-    pyproject_toml = f"""
+    pyproject_toml = """
     [build-system]
     requires = ["pdm-backend"]
     build-backend = "pdm.backend"