pythongh-121468: Fix the doctest failure for asyncio test on pdb (python#131258)

Author: gaogaotiantian

Lib/test/test_pdb.py

@@ -2079,7 +2079,7 @@ def test_pdb_asynctask():
             > <doctest test.test_pdb.test_pdb_asynctask[1]>(2)test()
             -> import pdb; pdb.Pdb(nosigint=True, readrc=False).set_trace()
             (Pdb) $_asynctask
-            <Task pending name='Task-1' coro=<test() running at <doctest test.test_pdb.test_pdb_asynctask[1]>:2> ...
+            <Task pending name=... coro=<test() running at <doctest test.test_pdb.test_pdb_asynctask[1]>:2> ...
             (Pdb) continue
             """