Fetch expanded data when toggle is clicked

What does this MR do and why?

Fetches expanded data when the toggle is clicked.

Screenshots or screen recordings

1. User clicks on the toggle button
2. Loading icon is displayed
3. Once loaded, the parent is updated and the expanded property of the object passed through v-model is updated.

How to set up and validate locally

1. This feature is behind a feature flag. Enable :refactor_security_extension to turn this feature on.

echo "Feature.enable(:refactor_security_extension)" | rails c

1. Visit an MR page with Security Scanning

The easiest way to populate data for testing is using this extension https://chrome.google.com/webstore/detail/mokku-mock-api-calls-seam/llflfcikklhgamfmnjkgpdadpmdplmji?hl=en and importing mokku-mocks-22-8-2022.json this json.

Once you have enabled the extension:

1. Open the developer tools
2. Find Mokku tab
3. Click on import
4. Import the file mentioned above

Apply the following patch to force triggering a request:

diff --git a/ee/app/assets/javascripts/vue_merge_request_widget/extensions/security_reports/mr_widget_security_reports.vue b/ee/app/assets/javascripts/vue_merge_request_widget/extensions/security_reports/mr_widget_security_reports.vue
index 04645dddb575..f8103dd413b4 100644
--- a/ee/app/assets/javascripts/vue_merge_request_widget/extensions/security_reports/mr_widget_security_reports.vue
+++ b/ee/app/assets/javascripts/vue_merge_request_widget/extensions/security_reports/mr_widget_security_reports.vue
@@ -98,7 +98,9 @@ export default {
       this.isLoading = value;
     },
 
-    fetchExpandedData() {},
+    fetchExpandedData() {
+      return this.fetchCollapsedData();
+    },
 
     fetchCollapsedData() {
       // TODO: check if gl.mrWidgetData can be safely removed after we migrate to the

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #368613 (closed)