Support Gitlab as a backend and also an IacSecrets implementaiotn

gitlab backend (https://docs.gitlab.com/ee/user/infrastructure/iac/terraform_state.html)
gitlab secrets
Add note that org.ysb33r.terraform.gitlab has been dropped.

Edited Feb 12, 2025 by Schalk W. Cronjé

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information