Deprecate v1 license metadata format

data/deprecations/16-9-deprecate-v1-license-metadata-format.yml

+- title: "Deprecate license metadata format V1"
+  removal_milestone: "17.0"
+  announcement_milestone: "16.9"
+  breaking_change: true
+  reporter: thiagocsf
+  stage: Secure
+  issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/438477
+  body: |  # (required) Don't change this line.
+    The license metadata format V1 dataset has been deprecated and will be removed
+    in GitLab 17.0.
+
+    Users who have the `package_metadata_synchronization` feature flag enabled are advised to
+    upgrade to GitLab 16.3 or above, and remove the feature flag configuration.

doc/update/deprecations.md

@@ -498,6 +498,24 @@ The runner's legacy escape sequence mechanism to handle variable expansion imple
 
 <div class="deprecation breaking-change" data-milestone="17.0">
 
+### Deprecate license metadata format V1
+
+<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/438477).
+</div>
+
+The license metadata format V1 dataset has been deprecated and will be removed
+in GitLab 17.0.
+
+Users who have the `package_metadata_synchronization` feature flag enabled are advised to
+upgrade to GitLab 16.3 or above, and remove the feature flag configuration.
+
+</div>
+
+<div class="deprecation breaking-change" data-milestone="17.0">
+
 ### Deprecated parameters related to custom text in the sign-in page
 
 <div class="deprecation-notes">