pythongh-109702: Increase concurrent_futures deadlock timeout (pythonGH-109703)

Replace SHORT_TIMEOUT with LONG_TIMEOUT in test_deadlock of
test_concurrent_futures.
(cherry picked from commit 1eb1b45)

Co-authored-by: Victor Stinner <[email protected]>

Author: vstinner

Lib/test/test_concurrent_futures/test_deadlock.py

@@ -88,7 +88,7 @@ def __reduce__(self):
 
 
 class ExecutorDeadlockTest:
-    TIMEOUT = support.SHORT_TIMEOUT
+    TIMEOUT = support.LONG_TIMEOUT
 
     def _fail_on_deadlock(self, executor):
         # If we did not recover before TIMEOUT seconds, consider that the