Migrate widget expand events to internal events

What does this MR do and why?

This is 3rd part of migrating code review events to internal events.

Type of Events	MR Link
view merge request	!156609 (merged)
click on full report merge request	!158454 (merged)
expand merge request	!158561 (merged) (We are here)

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

How to set up and validate locally

1. Apply below patch

diff --git a/app/assets/javascripts/vue_merge_request_widget/components/widget/app.vue b/app/assets/javascripts/vue_merge_request_widget/components/widget/app.vue
index e1d6b22b6f0fb..f01af75e3ec94 100644
--- a/app/assets/javascripts/vue_merge_request_widget/components/widget/app.vue
+++ b/app/assets/javascripts/vue_merge_request_widget/components/widget/app.vue
@@ -22,19 +22,19 @@ export default {
 
   computed: {
     testReportWidget() {
-      return this.mr.testResultsPath && 'MrTestReportWidget';
+      return 'MrTestReportWidget';
     },
 
     terraformPlansWidget() {
-      return this.mr.terraformReportsPath && 'MrTerraformWidget';
+      return 'MrTerraformWidget';
     },
 
     codeQualityWidget() {
-      return this.mr.codequalityReportsPath ? 'MrCodeQualityWidget' : undefined;
+      return 'MrCodeQualityWidget';
     },
 
     accessibilityWidget() {
-      return this.mr.accessibilityReportPath ? 'MrAccessibilityWidget' : undefined;
+      return 'MrAccessibilityWidget';
     },
 
     widgets() {
diff --git a/app/assets/javascripts/vue_merge_request_widget/components/widget/widget.vue b/app/assets/javascripts/vue_merge_request_widget/components/widget/widget.vue
index 7e66bb9036dab..acc0250ddafe4 100644
--- a/app/assets/javascripts/vue_merge_request_widget/components/widget/widget.vue
+++ b/app/assets/javascripts/vue_merge_request_widget/components/widget/widget.vue
@@ -225,7 +225,7 @@ export default {
   async mounted() {
     this.isLoadingCollapsedContent = true;
     this.telemetryHub?.viewed();
-
+    this.telemetryHub?.expanded({ type: this.summaryStatusIcon });
     try {
       if (this.fetchCollapsedData) {
         await this.fetch(this.fetchCollapsedData);

2. Open any merge request in local GDK.
3. it should send track_event API call with test_summary, terraform, code_quality and accessibility for expand event. Numbered steps to set up and validate the change are strongly suggested.

Related to #448283 (closed)