Merge #1989

1989: Fix #1988 r=mergify[bot] a=nextgens

## What type of PR?

bug-fix

## What does this PR do?

Fix a merge issue

### Related issue(s)
- close #1988


Co-authored-by: Florent Daigniere <nextgens@freenetproject.org>

core/admin/mailu/utils.py

@@ -58,7 +58,7 @@ def has_dane_record(domain, timeout=10):
         # we will receive this non-specific exception. The safe behaviour is to
         # accept to defer the email.
         flask.current_app.logger.warn(f'Unable to lookup the TLSA record for {domain}. Is the DNSSEC zone okay on https://dnsviz.net/d/{domain}/dnssec/?')
-        return app.config['DEFER_ON_TLS_ERROR']
+        return flask.current_app.config['DEFER_ON_TLS_ERROR']
     except dns.exception.Timeout:
         flask.current_app.logger.warn(f'Timeout while resolving the TLSA record for {domain} ({timeout}s).')
     except dns.resolver.NXDOMAIN: