Describe the bug
Hello, First, thanks a lot for your work.
I'm starting with checkmate (to replace checkcle that is having an issue on ressources, especially CPU) and I noticed the certificate expiry is not checked on https service with non-standard port.

To Reproduce
Steps to reproduce the behavior:

1. Go to Checkmate->Uptime->Create a monitor with a non standard https port (eg https://checkmate.example.org:54321
2. wait that the monitor is initialized and some checks are reported
3. Click on the monitor created
4. See error: Certificate Expiry is NA

Expected behavior
I would have expected the Certificate Expiry date to have been checked

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• Browser Chrome
• Version 147.0.7727.138

Additional context
Checkmate 3.7.1 running on Docker on a Synology DS1522+ (deployed using docker-compose mono with separated mongodb)