Disable PreCQ

Bug: chromium:953831
Change-Id: I976a99492eac9d2c3b59e7812a52c725861c5e8e
diff --git a/main.py b/main.py
index 9579753..4ea026e 100644
--- a/main.py
+++ b/main.py
@@ -70,6 +70,9 @@
   if not _RequestIsFromAppEngineCron():
     flask.abort(httplib.UNAUTHORIZED)
 
+  # Blunt force disable for PreCQ exonerator
+  return
+
   conn = cidb.CIDBConnection(
       config.cidb_cred_dir, for_service=config.is_service)
   all_exonerated = []