[PATCH] tests: update test-bundle2-format to pass import checker

[Augie Fackler]

# HG changeset patch
# User Augie Fackler <raf at durin42.com>
# Date 1503428751 14400
#      Tue Aug 22 15:05:51 2017 -0400
# Node ID 450e5c68b4f71f36ff011d972656c04416529dc4
# Parent  c9ae2f7cc20684a9340322dd949302bcf76fd70d
tests: update test-bundle2-format to pass import checker

diff --git a/tests/test-bundle2-format.t b/tests/test-bundle2-format.t
--- a/tests/test-bundle2-format.t
+++ b/tests/test-bundle2-format.t
@@ -12,8 +12,9 @@ Create an extension to test bundle2 API
   > This extension allows detailed testing of the various bundle2 API and
   > behaviors.
   > """
-  > 
-  > import sys, os, gc
+  > import gc
+  > import os
+  > import sys
   > from mercurial import util
   > from mercurial import bundle2
   > from mercurial import scmutil