Use gl-icon component for alert system notes

app/assets/javascripts/alert_management/components/system_notes/system_note.vue

 <script>
 /* eslint-disable vue/no-v-html */
+import { GlIcon } from '@gitlab/ui';
 import NoteHeader from '~/notes/components/note_header.vue';
-import { spriteIcon } from '~/lib/utils/common_utils';
 
 export default {
   components: {
     NoteHeader,
+    GlIcon,
   },
   props: {
     note: {
@@ -24,23 +25,23 @@ export default {
       } = this.note;
       return { ...author, id: id?.split('/').pop() };
     },
-    iconHtml() {
-      return spriteIcon(this.note?.systemNoteIconName);
-    },
   },
 };
 </script>
 
 <template>
-  <li :id="noteAnchorId" class="timeline-entry note system-note note-wrapper gl-px-0!">
-    <div class="timeline-entry-inner">
-      <div class="timeline-icon" v-html="iconHtml"></div>
-      <div class="timeline-content">
-        <div class="note-header">
-          <note-header :author="noteAuthor" :created-at="note.createdAt" :note-id="note.id">
-            <span v-html="note.bodyHtml"></span>
-          </note-header>
-        </div>
+  <li :id="noteAnchorId" class="timeline-entry note system-note note-wrapper gl-p-0!">
+    <div class="gl-display-inline-flex gl-align-items-center">
+      <div
+        class="gl-display-inline gl-bg-white gl-text-gray-200 gl-border-gray-100 gl-border-1 gl-border-solid gl-rounded-full gl-box-sizing-content-box gl-p-3 gl-mt-n2 gl-mr-6"
+      >
+        <gl-icon :name="note.systemNoteIconName" />
+      </div>
+
+      <div class="note-header">
+        <note-header :author="noteAuthor" :created-at="note.createdAt" :note-id="note.id">
+          <span v-html="note.bodyHtml"></span>
+        </note-header>
       </div>
     </div>
   </li>

app/assets/stylesheets/pages/alert_management/details.scss

@@ -33,7 +33,7 @@
   }
 
   .main-notes-list::before {
-    left: 15px !important;
+    left: $gl-spacing-scale-5 !important;
   }
 
   .note-header-info {

spec/frontend/alert_management/components/system_notes/alert_management_system_note_spec.js

 import { shallowMount } from '@vue/test-utils';
+import { GlIcon } from '@gitlab/ui';
 import SystemNote from '~/alert_management/components/system_notes/system_note.vue';
 import mockAlerts from '../../mocks/alerts.json';
 
@@ -19,6 +20,7 @@ describe('Alert Details System Note', () => {
   afterEach(() => {
     if (wrapper) {
       wrapper.destroy();
+      wrapper = null;
     }
   });
 
@@ -29,10 +31,10 @@ describe('Alert Details System Note', () => {
 
     it('renders the correct system note', () => {
       const noteId = wrapper.find('.note-wrapper').attributes('id');
-      const iconRoute = wrapper.find('use').attributes('href');
+      const iconName = wrapper.find(GlIcon).attributes('name');
 
       expect(noteId).toBe('note_1628');
-      expect(iconRoute.includes('user')).toBe(true);
+      expect(iconName).toBe(mockAlert.notes.nodes[0].systemNoteIconName);
     });
   });
 });