bisect-kit: fix format

BUG=None
TEST=None

Change-Id: I5754099c86257ad702ea1ef8ba68d777111ca544
Reviewed-on: https://chromium-review.googlesource.com/1880403
Tested-by: Kuang-che Wu <kcwu@chromium.org>
Commit-Ready: Zheng-Jie Chang <zjchang@chromium.org>
Commit-Ready: Kuang-che Wu <kcwu@chromium.org>
Legacy-Commit-Queue: Commit Bot <commit-bot@chromium.org>
Reviewed-by: Zheng-Jie Chang <zjchang@chromium.org>
Reviewed-by: Kuang-che Wu <kcwu@chromium.org>
diff --git a/bisect_kit/codechange.py b/bisect_kit/codechange.py
index 7c9701e..0e5bc68 100644
--- a/bisect_kit/codechange.py
+++ b/bisect_kit/codechange.py
@@ -931,8 +931,8 @@
     cache_dir = os.path.join(self.root_dir, _DIFF_CACHE_DIR)
     cache_filename = os.path.join(cache_dir, '%s,%s.json' % (old, new))
     if not os.path.exists(cache_filename):
-      raise errors.InternalError('cached revlist not found: %s' %
-                                 cache_filename)
+      raise errors.InternalError(
+          'cached revlist not found: %s' % cache_filename)
 
     result = []
     for data in json.load(open(cache_filename)):