logging: use cros_logging instead of logging

Replace all instances of import logging in chromite with cros_logging.

BUG=brillo:615
TEST=unittests + trybot
CQ-DEPEND=CL:260455

Change-Id: I3cf7ad9301290e736de2eebea00e9085656a2d5b
Reviewed-on: https://chromium-review.googlesource.com/261311
Reviewed-by: Don Garrett <dgarrett@chromium.org>
Commit-Queue: Ralph Nathan <ralphnathan@chromium.org>
Tested-by: Ralph Nathan <ralphnathan@chromium.org>
diff --git a/scripts/autotest_quickmerge.py b/scripts/autotest_quickmerge.py
index 347df38..4787312 100644
--- a/scripts/autotest_quickmerge.py
+++ b/scripts/autotest_quickmerge.py
@@ -12,7 +12,6 @@
 
 import argparse
 import glob
-import logging
 import os
 import re
 import sys
@@ -20,6 +19,7 @@
 
 from chromite.cbuildbot import constants
 from chromite.lib import cros_build_lib
+from chromite.lib import cros_logging as logging
 from chromite.lib import git
 from chromite.lib import osutils
 from chromite.lib import portage_util