bpo-40826: Fix test_repl.test_close_stdin() on Windows (GH-20779) (GH-20785)

test_repl.test_close_stdin() now calls
support.suppress_msvcrt_asserts() to fix the test on Windows.

* Move suppress_msvcrt_asserts() from test.libregrtest.setup to
  test.support. Make its verbose parameter optional: verbose=False by
  default.
* SuppressCrashReport now uses SetErrorMode() of the msvcrt module,
  rather than using ctypes.
* Remove also an unused variable (deadline) in wait_process().

(cherry picked from commit f6e58aefde2e57e4cb11ea7743955da53a3f1e80)
diff --git a/Lib/test/test_repl.py b/Lib/test/test_repl.py
index 563f188..03bf8d8 100644
--- a/Lib/test/test_repl.py
+++ b/Lib/test/test_repl.py
@@ -98,7 +98,11 @@
             print("before close")
             os.close(0)
         ''')
-        process = spawn_repl()
+        prepare_repl = dedent('''
+            from test.support import suppress_msvcrt_asserts
+            suppress_msvcrt_asserts()
+        ''')
+        process = spawn_repl('-c', prepare_repl)
         output = process.communicate(user_input)[0]
         self.assertEqual(process.returncode, 0)
         self.assertIn('before close', output)