bisect-kit: fix bug: repo sync failed when manifest is moved

BUG=b:149590000
TEST=manually

Change-Id: I07519dbc65e3caa353119e6654b9bf294eb2bc1d
diff --git a/bisect_kit/git_util.py b/bisect_kit/git_util.py
index fbb79f8..5ae6ede 100644
--- a/bisect_kit/git_util.py
+++ b/bisect_kit/git_util.py
@@ -633,7 +633,8 @@
           appeared = commit_time
       else:
         if appeared:
-          dependencies.append((include, appeared, commit_time))
+          # dependency file exists in time range [appeared, commit_time)
+          dependencies.append((include, appeared, commit_time - 1))
           appeared = None
 
     if appeared is not None: