Fix ipv6 cert cannot be found

[Fangliding]

the old code only check the folder with "." for di in "${CERT_HOME}"/*.*/; do
if we have a ipv6 ip cert like this 2001:db8::_ecc
because it doesn't contain "." it cannot be found and renewed

[Fangliding]

But this will cause the log to display some incorrect folders (although they are safely skipped)

[Wed Aug 20 05:53:38 AM BST 2025] Renewing: 'ca'
[Wed Aug 20 05:53:38 AM BST 2025] 'ca' is not an issued domain, skipping.
[Wed Aug 20 05:53:38 AM BST 2025] Skipped ca
[Wed Aug 20 05:53:38 AM BST 2025] Renewing: 'deploy'
[Wed Aug 20 05:53:38 AM BST 2025] 'deploy' is not an issued domain, skipping.
[Wed Aug 20 05:53:38 AM BST 2025] Skipped deploy
[Wed Aug 20 05:53:38 AM BST 2025] Renewing: 'dnsapi'
[Wed Aug 20 05:53:38 AM BST 2025] 'dnsapi' is not an issued domain, skipping.
[Wed Aug 20 05:53:38 AM BST 2025] Skipped dnsapi
[Wed Aug 20 05:53:38 AM BST 2025] Renewing: 'notify'
[Wed Aug 20 05:53:38 AM BST 2025] 'notify' is not an issued domain, skipping.
[Wed Aug 20 05:53:38 AM BST 2025] Skipped notify

shall we skip this 4 folders?