Remove lets_encrypt_private_key from secrets
Let's Encrypt private key was moved to application_settings: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/28353
This MR removes private key added in:
Edited by Vladimir Shushlin
Let's Encrypt private key was moved to application_settings: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/28353
This MR removes private key added in: