Note resets only legacy numpy random state

Author: adamchainz

README.rst

@@ -50,8 +50,10 @@ All of these features are on by default but can be disabled with flags.
   fixture
   (`docs <https://faker.readthedocs.io/en/master/pytest-fixtures.html#seeding-configuration>`__).
 
-* If `numpy <http://www.numpy.org/>`_ is installed, its global random state is
-  reset at the start of every test.
+* If `numpy <http://www.numpy.org/>`_ is installed, its legacy global random state in |numpy.random|__ is reset at the start of every test.
+
+  .. |numpy.random| replace:: ``numpy.random``
+  __ https://numpy.org/doc/stable/reference/random/index.html
 
 * If additional random generators are used, they can be registered under the
   ``pytest_randomly.random_seeder``