Drop hack required for AFIP's insecure DH ciphers

[WhyNotHugo]

Many months back AFIP made changes to their servers which resulted in substandard security (particularly, they switched to using only insecure cyphers).

Regrettably, they seemed incapable (or unwilling) to understand and fix the issue, so we added a hack to enable establishing insecure connections. With their recent changes to upgrade the used TLS version, it's possible they've also fixed this (I definitely hope so).

If I recall correctly, the security downgrade only applied to production, so this also needs to be tested in production before being merged.