gh-150818: Skip new test where threading is unavailable

WASI and Emscripten have no working threading, so guard the regression
test with requires_working_threading(), matching the other thread-using
tests in test_logging.

Author: gaborbernat

Lib/test/test_logging.py

@@ -4269,6 +4269,7 @@ def test_set_log_record_factory(self):
         man.setLogRecordFactory(expected)
         self.assertEqual(man.logRecordFactory, expected)
 
+    @threading_helper.requires_working_threading()
     def test_getLogger_fast_path_never_returns_unwired_logger(self):
         # getLogger()'s lock-free fast path returns a logger straight out of
         # loggerDict, so a logger must be published there only after