Merge request webhook missing changes when changing target branch

Summary

When changing target_branch, the changes object in the merge request webhook only contains merge_status and loses any other properties changed

What is the current behavior?

The changes object, at most, only contains merge_status

  "changes": {
    "merge_status": {
      "previous": "can_be_merged",
      "current": "unchecked"
    }
  },

What is the expected correct behavior?

the changes object should contain target_branch and any other properties that were changed at the same time

  "changes": {
    "merge_status": {
      "previous": "can_be_merged",
      "current": "unchecked"
    },
    "last_edited_at": {
      "previous": "2020-06-25 20:12:17 UTC",
      "current": "2020-06-25 20:13:35 UTC"
    },
    "title": {
      "previous": "before example",
      "current": "after example"
    },
    "target_branch": {
      "previous": "old_branch_name",
      "current": "new_branch_name"
    }
  },