Ignore errors doesn't work in duplicity 6.23 and 7.0

--ignore_errors option doesn't work in 6.23 and 7.0

This can be traced to missing underscore as below

@@ -379,7 +379,7 @@
                       callback = lambda o, s, v, p: (log.Warn(
                           _("Running in 'ignore errors' mode due to %s; please "
                             "re-consider if this was not intended") % s),
- setattr(p.values, "ignore errors", True)))
+ setattr(p.values, "ignore_errors", True)))

     # Whether to use the full email address as the user name when
     # logging into an imap server. If false just the user name