Edit digest separately despite GCM cipher

[keeshux]

I also noticed that if I change the 'Cipher' to CBC, the 'Authentication' type chosen is what the debug log lists under 'Digest' when switching the Cipher from CBC to GCM. E.g., If I choose AES-256-CBC and HMAC-SHA1, change Cipher to AES-256-GCM, and attempt to connect, then the Debug log lists Digest: HMAC-SHA1.

Digest is also used for --tls-auth, so leave it editable regardless of the cipher.