[TLS 1.2, TLS 1.3] Fail immediately if server sends empty certificate message for TLS 1.2 and beyond

[AlexLanzano]

Description

For TLS 1.2, the client accepts an empty certificate message from the server. This violates RFC 5246 section 7.4.2. However, for TLS 1.3 the client will properly fail immediately when receiving an empty certificate message from the server.

So to fix this, I modified the empty cert check to include both TLS 1.2 and TLS 1.3.

Fixes #9651

Testing

Reproduction steps in #9651

[SparkiDev]

How is accepting an empty ServerCertificate message violating RFC 5246 7.4.2?
I think you mean for non-anonymous cipher suites this is invalid. Which means you need to check the cipher suite before failing in the TLS 1.2 case.