Terraform enabled by default, remove extra enablement

doc/administration/terraform_state.md

@@ -26,7 +26,6 @@ below.
    `/etc/gitlab/gitlab.rb` and add the following line:
 
    ```ruby
-   gitlab_rails['terraform_state_enabled'] = true
    gitlab_rails['terraform_state_storage_path'] = "/mnt/storage/terraform_state"
    ```
 
@@ -76,7 +75,6 @@ See [the available connection settings for different providers](object_storage.m
    the values you want:
 
    ```ruby
-   gitlab_rails['terraform_state_enabled'] = true
    gitlab_rails['terraform_state_object_store_enabled'] = true
    gitlab_rails['terraform_state_object_store_remote_directory'] = "terraform"
    gitlab_rails['terraform_state_object_store_connection'] = {