catch bad symlink in assert

Author: dylanjew

src/local/butler/common.py

@@ -93,7 +93,7 @@ def _get_clusterfuzz_config_commit_sha():
 
 def _compute_revision(timestamp, is_staging=False):
   """Return a source code revision.
-   
+
   This revision contains the timestamp, git-sha, user, config git-sha, and
   appengine release (prod or staging). The ordinality of revision is crucial
   for updating source code. Later revision *must* be greater than earlier