Use IgnoreEndRevocationUnknown

[rido-min]

When validating TLS connections, we dont want to configure the Revocation as NoCheck. Instead, we could use the IgnoreEndRevocationUnknown flag.

[CIPop]

The change is reducing security when using CA certificates and that should be:

1. Clear within the code: comment, function name should be renamed to "Unsafe..."
2. Audit-ready: a warning-level trace should outline the fact that CA revocation is now disabled.

[rido-min]

I've added traces in fde2823

and also found that we need an additional Ignore flag:

MqttApplicationSamples/mqttclients/dotnet/MQTTnet.Client.Extensions/X509ChainValidator.cs

Line 35 in fde2823

cvArgs.Chain.ChainPolicy.VerificationFlags = X509VerificationFlags.IgnoreEndRevocationUnknown | X509VerificationFlags.IgnoreCertificateAuthorityRevocationUnknown;

I want to investigate more to understand those flags before merging