test(replay): re-enable replay-details test which asserts the page does load (#56498)

<!-- Describe your PR here. -->

tests/acceptance/test_replay_detail.py

@@ -1,7 +1,5 @@
 from datetime import datetime, timedelta
 
-import pytest
-
 from sentry.replays.testutils import (
     mock_replay,
     mock_rrweb_div_helloworld,
@@ -77,7 +75,6 @@ class ReplayDetailTest(ReplaysAcceptanceTestCase):
             self.browser.get(self.path)
             self.browser.wait_until_not('[data-test-id="loading-indicator"]')
 
-    @pytest.mark.skip(reason="flaky: https://github.com/getsentry/sentry/issues/42263")
     def test_simple(self):
         with self.feature(FEATURE_NAME):
             self.browser.get(self.path)