Better error message for expired client certificates

[liquidiert]

What is the new feature about?

Currently when you have an expired certificate in your client file and try to connect with that the connection just times out and sets the connection into error state. We should probably expand on the error message hinting to an expired cert.

Why would such a feature be important to you?

Because I could not connect and this issue is kind of not nice

Anything else we need to know?

No response