[ACME] Fix wildcard certificate conflict with MAILCOW_HOSTNAME

[FreddleSpl0it]

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What does this PR include?

Short Description

Fixes ACME DNS-01 challenge failures when using wildcard certificates that cover the MAILCOW_HOSTNAME. Previously, when ADDITIONAL_SAN contained a wildcard domain (e.g., *.example.com) and MAILCOW_HOSTNAME was a subdomain of that wildcard (e.g., mail.example.com), Let's Encrypt would reject the certificate request with the error: "Domain name 'mail.example.com' is redundant with a wildcard domain in the same request."

This PR adds detection to skip adding MAILCOW_HOSTNAME to the certificate request when it's already covered by a wildcard in ADDITIONAL_SAN.

Fixes:

• ACME: DNS-01 Challenge and Wildcard Domains #7112

Affected Containers

• acme-mailcow

[svengo]

The patch fixes the problem for me. Thank you!