match latest config from https://cipherli.st/

Updated ciphers and SSL settings to match latest recommendation by @RaymiiOrg on https://cipherli.st. Replaces https://github.com/gitlabhq/gitlabhq/pull/8019.

/cc @maxlazio @dosire
Explanation of `builtin:1000` removal: https://github.com/RaymiiOrg/cipherli.st/pull/20