fix: reset console pages in the index tests

A Sony fixture split by console recorded its pages in the shared map, and the index tests that ran after it linked PlayStation to the split page. They now start from an empty map, and the fixture clears it when done.

tests/test_site_r2_emulators.py

@@ -165,6 +165,9 @@ class TheSummaryLineIsProse(unittest.TestCase):
 
 class TheIndexNamesEmulatorsAndSystems(unittest.TestCase):
     def test_columns_and_counts(self):
+        # Pages another test split off would send the console elsewhere.
+        siterender.reset_console_pages()
+        self.addCleanup(siterender.reset_console_pages)
         saved = dict(siterender._system_page_map)
         self.addCleanup(siterender.set_system_page_map, saved)
         siterender.set_system_page_map({"sony-playstation": ("sony", "PlayStation")})