Replace import_fresh_module in decimal test files (GH-21815)

Modules/_decimal/tests/bench.py

@@ -7,13 +7,10 @@
 
 
 import time
-try:
-    from test.support import import_fresh_module
-except ImportError:
-    from test.test_support import import_fresh_module
 
-C = import_fresh_module('decimal', fresh=['_decimal'])
-P = import_fresh_module('decimal', blocked=['_decimal'])
+import _decimal as C
+import _pydecimal as P
+
 
 #
 # NOTE: This is the pi function from the decimal documentation, modified

Modules/_decimal/tests/deccheck.py

@@ -43,7 +43,6 @@ from subprocess import PIPE, STDOUT
 from queue import Queue, Empty
 from threading import Thread, Event, Lock
 
-from test.support import import_fresh_module
 from randdec import randfloat, all_unary, all_binary, all_ternary
 from randdec import unary_optarg, binary_optarg, ternary_optarg
 from formathelper import rand_format, rand_locale
@@ -52,8 +51,10 @@ from _pydecimal import _dec_from_triple
 from _testcapi import decimal_as_triple
 from _testcapi import decimal_from_triple
 
-C = import_fresh_module('decimal', fresh=['_decimal'])
-P = import_fresh_module('decimal', blocked=['_decimal'])
+import _decimal as C
+import _pydecimal as P
+
+
 EXIT_STATUS = 0
 
 

Modules/_decimal/tests/formathelper.py

@@ -31,11 +31,10 @@
 
 import os, sys, locale, random
 import platform, subprocess
-from test.support import import_fresh_module
 from distutils.spawn import find_executable
 
-C = import_fresh_module('decimal', fresh=['_decimal'])
-P = import_fresh_module('decimal', blocked=['_decimal'])
+import _decimal as C
+import _pydecimal as P
 
 
 windows_lang_strings = [