Don't exit with error on HTTP 401 when downloading clone bundle

If the server returns HTTP 401 (unauthorized) when attempting to
download clone bundle files, ignore it and continue, rather than
exiting with a fatal error.

Change-Id: I2c7ee03e149c354c7e4ad6ea1ebf266534778fe1

repo

@@ -462,7 +462,7 @@ def _DownloadBundle(url, local, quiet):
     try:
       r = urllib.request.urlopen(url)
     except urllib.error.HTTPError as e:
-      if e.code in [403, 404]:
+      if e.code in [401, 403, 404]:
         return False
       _print('fatal: Cannot get %s' % url, file=sys.stderr)
       _print('fatal: HTTP error %s' % e.code, file=sys.stderr)