bpo-16079: fix duplicate test method name in test_gzip. (GH-12827)

(cherry picked from commit cd46655)

Co-authored-by: Gregory P. Smith <greg@krypto.org>

Author: miss-islington

Lib/test/test_gzip.py

@@ -735,7 +735,7 @@ def test_compress_stdin_outfile(self):
         self.assertEqual(out[:2], b"\x1f\x8b")
 
     @create_and_remove_directory(TEMPDIR)
-    def test_compress_infile_outfile(self):
+    def test_compress_infile_outfile_default(self):
         local_testgzip = os.path.join(TEMPDIR, 'testgzip')
         gzipname = local_testgzip + '.gz'
         self.assertFalse(os.path.exists(gzipname))