cope with older py-test-mock

Index: guessit/test/test_api.py
--- guessit/test/test_api.py.orig
+++ guessit/test/test_api.py
@@ -6,7 +6,7 @@ import os
 from pathlib import Path
 
 import pytest
-from pytest_mock import MockerFixture
+from pytest_mock import MockFixture
 
 from .. import api
 from ..api import guessit, properties, suggested_expected, GuessitException, default_api
@@ -70,7 +70,7 @@ def test_suggested_expected():
     assert actual == content['suggested']
 
 
-def test_should_rebuild_rebulk_on_advanced_config_change(mocker: MockerFixture):
+def test_should_rebuild_rebulk_on_advanced_config_change(mocker: MockFixture):
     api.reset()
     rebulk_builder_spy = mocker.spy(api, 'rebulk_builder')
 
@@ -93,7 +93,7 @@ def test_should_rebuild_rebulk_on_advanced_config_chan
     rebulk_builder_spy.reset_mock()
 
 
-def test_should_not_rebuild_rebulk_on_same_advanced_config(mocker: MockerFixture):
+def test_should_not_rebuild_rebulk_on_same_advanced_config(mocker: MockFixture):
     api.reset()
     rebulk_builder_spy = mocker.spy(api, 'rebulk_builder')
 
