Announce deprecation for `fmt` job in Terraform Module template

data/deprecations/16-9-deprecate-terraform-module-fmt-job.yml

+- title: "Deprecate `fmt` job in Terraform Module CI/CD template"
+  # The milestones for the deprecation announcement, and the removal.
+  removal_milestone: "17.0"
+  announcement_milestone: "16.9"
+  # Change breaking_change to false if needed.
+  breaking_change: true
+  # The stage and GitLab username of the person reporting the change,
+  # and a link to the deprecation issue
+  reporter: timofurrer
+  stage: deploy
+  issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/440249
+  body: |  # (required) Don't change this line.
+    The `fmt` job in the Terraform Module CI/CD templates is deprecated and will be removed in GitLab 17.0.
+    This affects the following templates:
+
+    - `Terraform-Module.gitlab-ci.yml`
+    - `Terraform/Module-Base.gitlab-ci.yml`
+
+    You can manually add back a Terraform `fmt` job to your pipeline using:
+
+    ```yaml
+    fmt:
+      image: hashicorp/terraform
+      script: terraform fmt -chdir "$TF_ROOT" -check -diff -recursive
+    ```
+
+    You can also use the `fmt` template from the [OpenTofu CI/CD component](https://gitlab.com/components/opentofu).

doc/update/deprecations.md

@@ -560,6 +560,34 @@ These fields (`architectureName`, `ipAddress`, `platformName`, `revision`, `vers
 
 <div class="deprecation breaking-change" data-milestone="17.0">
 
+### Deprecate `fmt` job in Terraform Module CI/CD template
+
+<div class="deprecation-notes">
+- Announced in GitLab <span class="milestone">16.9</span>
+- Removal in GitLab <span class="milestone">17.0</span> ([breaking change](https://docs.gitlab.com/ee/update/terminology.html#breaking-change))
+- To discuss this change or learn more, see the [deprecation issue](https://gitlab.com/gitlab-org/gitlab/-/issues/440249).
+</div>
+
+The `fmt` job in the Terraform Module CI/CD templates is deprecated and will be removed in GitLab 17.0.
+This affects the following templates:
+
+- `Terraform-Module.gitlab-ci.yml`
+- `Terraform/Module-Base.gitlab-ci.yml`
+
+You can manually add back a Terraform `fmt` job to your pipeline using:
+
+```yaml
+fmt:
+  image: hashicorp/terraform
+  script: terraform fmt -chdir "$TF_ROOT" -check -diff -recursive
+```
+
+You can also use the `fmt` template from the [OpenTofu CI/CD component](https://gitlab.com/components/opentofu).
+
+</div>
+
+<div class="deprecation breaking-change" data-milestone="17.0">
+
 ### Deprecate `message` field from Vulnerability Management features
 
 <div class="deprecation-notes">