HTTPS filtering original certificate caching algorithm

[ameshkov]

It seems that currently, we don't update the target server's cert when the target server cert's common name is changed.

This leads to the fact that I am seeing the same old cert when inspecting it via the browser assistant.

Steps to reproduce:

1. Set up a server with some cert (for instance, CN=testdomain.yourdomain.org)
2. Open it with AG enabled, inspect the original cert via the browser assistant extension
3. Replace the old cert with a new one (for instance, CN=*.yourdomain.org)
4. Reload the website and check what cert you're seeing via the browser assistant.