Merge branch 'build-notification-null-check' into 'master'

Stop CI notification showing when status is nil

See merge request !10044

app/assets/javascripts/merge_request_widget.js

@@ -176,7 +176,7 @@ import MiniPipelineGraph from './mini_pipeline_graph_dropdown';
               _this.opts.ci_sha = data.sha;
               _this.updateCommitUrls(data.sha);
             }
-            if (showNotification) {
+            if (showNotification && data.status) {
               status = _this.ciLabelForStatus(data.status);
               if (status === "preparing") {
                 title = _this.opts.ci_title.preparing;