Fixed toggling draft state showing wrong state

Fixes the wrong state being shown after toggling the draft state
from inside the widget.

Closes https://gitlab.com/gitlab-org/gitlab/-/issues/323688

app/assets/javascripts/vue_merge_request_widget/components/states/work_in_progress.vue

@@ -70,7 +70,7 @@ export default {
               data: {
                 mergeRequestSetWip: {
                   errors,
-                  mergeRequest: { workInProgress, title },
+                  mergeRequest: { mergeableDiscussionsState, workInProgress, title },
                 },
               },
             },
@@ -87,6 +87,8 @@ export default {
             });
 
             const data = produce(sourceData, (draftState) => {
+              // eslint-disable-next-line no-param-reassign
+              draftState.project.mergeRequest.mergeableDiscussionsState = mergeableDiscussionsState;
               // eslint-disable-next-line no-param-reassign
               draftState.project.mergeRequest.workInProgress = workInProgress;
               // eslint-disable-next-line no-param-reassign
@@ -107,6 +109,7 @@ export default {
               errors: [],
               mergeRequest: {
                 __typename: 'MergeRequest',
+                mergeableDiscussionsState: true,
                 title: this.mr.title,
                 workInProgress: false,
               },

app/assets/javascripts/vue_merge_request_widget/queries/toggle_wip.mutation.graphql

 mutation toggleWIPStatus($projectPath: ID!, $iid: String!, $wip: Boolean!) {
   mergeRequestSetWip(input: { projectPath: $projectPath, iid: $iid, wip: $wip }) {
     mergeRequest {
+      mergeableDiscussionsState
       title
       workInProgress
     }