bpo-44949: Fix test_readline auto history tests (GH-27813)

(cherry picked from commit 6fb62b42f4db56ed5efe0ca4c1059049276c1083)

Co-authored-by: Victor Stinner <vstinner@python.org>
diff --git a/Lib/test/test_readline.py b/Lib/test/test_readline.py
index f3e404d..e8fb8d2 100644
--- a/Lib/test/test_readline.py
+++ b/Lib/test/test_readline.py
@@ -156,11 +156,15 @@ def test_init(self):
 
     def test_auto_history_enabled(self):
         output = run_pty(self.auto_history_script.format(True))
-        self.assertIn(b"History length: 1\r\n", output)
+        # bpo-44949: Sometimes, the newline character is not written at the
+        # end, so don't expect it in the output.
+        self.assertIn(b"History length: 1", output)
 
     def test_auto_history_disabled(self):
         output = run_pty(self.auto_history_script.format(False))
-        self.assertIn(b"History length: 0\r\n", output)
+        # bpo-44949: Sometimes, the newline character is not written at the
+        # end, so don't expect it in the output.
+        self.assertIn(b"History length: 0", output)
 
     def test_nonascii(self):
         loc = locale.setlocale(locale.LC_CTYPE, None)