lint: clean up use of \ as line continuation

We prefer hanging indents over \ whenever possible.  Clean things up
to use hanging indents or specific () or even omit things entirely as
the code as-is doesn't need the explicit \.

BUG=None
TEST=`cros lint` is clean & `./run_tests` passes

Change-Id: I03dbdeaba11c159a6a6ad2399037643fea361407
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/2766442
Reviewed-by: Sergey Frolov <sfrolov@google.com>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
diff --git a/scripts/sysmon/git_metrics_unittest.py b/scripts/sysmon/git_metrics_unittest.py
index 71c4492..58341df 100644
--- a/scripts/sysmon/git_metrics_unittest.py
+++ b/scripts/sysmon/git_metrics_unittest.py
@@ -36,8 +36,8 @@
   def test_collect(self):
     with mock.patch.object(git_metrics, '_GitRepo', autospec=True) as _GitRepo:
       instance = _GitRepo('dummy')
-      instance.get_commit_hash.return_value = \
-          '2b1ce059425edc91e013c260e59019195f927a07'
+      instance.get_commit_hash.return_value = (
+          '2b1ce059425edc91e013c260e59019195f927a07')
       instance.get_commit_time.return_value = 1483257600
       instance.get_unstaged_changes.return_value = (0, 3)