Issue #28664: test_bz2 now works on non-Windows platforms without bunzip2

(e.g. on Android).

diff --cc Lib/test/test_bz2.py
index 482242c00e33b8256d9b2433db21e6943fc05788,34f6478356fe83e0eb43747f7b38f396713a1029..eaa472a6ccda03264de500cb4c5e78b2062f3a69
--- 1/Lib/test/test_bz2.py
--- 2/Lib/test/test_bz2.py
+++ b/Lib/test/test_bz2.py
@@@ -6,8 -6,8 +6,9 @@@ from io import BytesIO, DEFAULT_BUFFER_
  import os
  import pickle
  import glob
 +import pathlib
  import random
+ import shutil
  import subprocess
  import sys
  from test.support import unlink