Improve test docstring for intree backend

tests/test_inplace_hooks.py

@@ -71,9 +71,10 @@ def test_intree_backend_loaded_from_correct_backend_path():
  """
  PEP 517 establishes that the backend code should be loaded from ``backend-path``,
  and recognizes that not always the environment isolation is perfect
- (e.g. it explicitly mentions ``--system-site-packages``). Therefore, even in a
- situation where a ``MetaPathFinder`` would have priority to find the backend spec,
- the backend should still be loaded from ``backend-path``.
+ (e.g. it explicitly mentions ``--system-site-packages``).
+ Therefore, even in a situation where a third-party ``MetaPathFinder`` has
+ precedence over ``importlib.machinery.PathFinder``, the backend should
+ still be loaded from ``backend-path``.
  """
  hooks = get_hooks("pkg_intree", backend="intree_backend")
  with TemporaryDirectory() as tmp: