opentelemetry-sdk: make test_force_flush_late_by_timeout less flaky on pypy/windows (#5102)

Timers on pypy/windows are more coarse than what we expect so give it a
bit more room.

Author: xrmx

opentelemetry-sdk/tests/trace/test_span_processor.py

@@ -461,7 +461,7 @@ def delayed_flush(_):
         for mock_processor in mocks:
             multi_processor.add_span_processor(mock_processor)
 
-        flushed = multi_processor.force_flush(timeout_millis=10)
+        flushed = multi_processor.force_flush(timeout_millis=25)
         # let the thread executing the late_mock continue
         wait_event.set()