Merge branch 'ph/mrDashboardTransparentAvatars' into 'master'

Fixes the background of transparent avatars in the merge request dashboard

See merge request !165205



Merged-by: Jose Ivan Vargas <jvargas@gitlab.com>
Approved-by: Jose Ivan Vargas <jvargas@gitlab.com>
Co-authored-by: Phil Hughes <me@iamphill.com>

app/assets/javascripts/merge_request_dashboard/components/assigned_users.vue

@@ -136,7 +136,7 @@ export default {
           class="gl-relative"
           data-testid="assigned-user"
         >
-          <gl-avatar :src="user.avatarUrl" :size="32" />
+          <gl-avatar :src="user.avatarUrl" :size="32" class="!gl-bg-white" />
           <span
             v-if="isCurrentUser(user)"
             class="gl-absolute -gl-left-2 -gl-top-2 gl-flex gl-h-5 gl-w-5 gl-items-center gl-justify-center gl-rounded-full gl-bg-blue-500 gl-p-1 gl-text-white"

spec/frontend/merge_request_dashboard/components/__snapshots__/assigned_users_spec.js.snap

@@ -36,7 +36,7 @@ exports[`Merge request dashboard assigned users component renders user avatars 1
       >
         <img
           alt="avatar"
-          class="gl-avatar gl-avatar-circle gl-avatar-s32"
+          class="!gl-bg-white gl-avatar gl-avatar-circle gl-avatar-s32"
           src="/root"
         />
         <span
@@ -67,7 +67,7 @@ exports[`Merge request dashboard assigned users component renders user avatars 1
       >
         <img
           alt="avatar"
-          class="gl-avatar gl-avatar-circle gl-avatar-s32"
+          class="!gl-bg-white gl-avatar gl-avatar-circle gl-avatar-s32"
           src="/root"
         />
         <span