Configuration: https://mta-sts.de.bauer-group.com/.well-known/mta-sts.txt
Mandatory DNS Entry: _mta-sts TXT "v=STSv1; id=20230101000000"
Optional Reporting DNS Entry: _smtp._tls TXT "v=TLSRPTv1; rua=mailto:mta-sts@bauer-group.com"