Added documentation for new terraform list actions

doc/user/infrastructure/terraform_state.md

@@ -347,14 +347,62 @@ location. You can then go back to running it from within GitLab CI.
 NOTE:
 We are currently working on [providing a graphical interface for managing state files](https://gitlab.com/groups/gitlab-org/-/epics/4563).
 
-![Terraform state list](img/terraform_list_view_v13_5.png)
+![Terraform state list](img/terraform_list_view_v13_8.png)
 
-The state files attached to a project can be found under Operations / Terraform.
+To list the state files attached to a project go to **Operations > Terraform**.
 
-## Removing a State file
+![Terraform state list](img/terraform_list_view_actions_v13_8.png)
 
-You can only remove a state file by making a request to the API, like the following example:
+The list also includes an **Actions** column where you can download, lock or unlock, or remove each state file.
+
+## Remove a state file
+
+You can use the following options to remove a state file:
+
+1. GitLab REST API
+1. GitLab GraphQL API
+1. GitLab UI
+
+### Remove a state file with the GitLab REST API
+
+You can remove a state file by making a request to the REST API, for example:
 
 ```shell
 curl --header "Private-Token: <your_access_token>" --request DELETE "https://gitlab.example.com/api/v4/projects/<your_project_id>/terraform/state/<your_state_name>"
 ```
+
+### Remove a state file with the GitLab GraphQL API
+
+You can remove a state file by making a GraphQL API request, for example:
+
+```shell
+mutation deleteState {
+  terraformStateDelete(input: { id: "<global_id_for_the_state>" }) {
+    errors
+  }
+}
+```
+
+You can obtain the <global_id_for_the_state> by querying the list of states. For example:
+
+```shell
+query ProjectTerraformStates {
+  project(fullPath: "<your_project_path>") {
+    terraformStates {
+      nodes {
+        id
+        name
+      }
+    }
+  }
+}
+```
+
+For those new to the GitLab GraphQL API, see [Getting started with GitLab GraphQL API](../../api/graphql/getting_started.md).
+
+### Remove a state file with the GitLab UI
+
+To delete a state file:
+
+- From your project, go to **Operations > Terraform**.
+- In the **Actions** column, click on the vertical ellipsis (**{ellipsis_v}**) button and select **Remove state file and versions**.