Initials icon of MB post in Search portlet results displays by incorrect user initials

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: Master
• Fix Version/s: 7.0.0 DXP FP18, 7.0.3 CE GA4, 7.0.0 DXP SP4, 7.0.X EE, 7.1.X, Master
• Component/s: Web Search > Search Widgets
• Labels:
  • backend_test
  • jp-support
  • liferay-digital-enterprise-70-sp4
  • liferay-fixpack-de-18-7010
• Branch Version/s:
  7.0.x
• Backported to Branch:
  Committed
• Story Points: 1
• Fix Priority: 4
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/48503

Summary
In Message Boards panel, MB thread displays initials icons using initials of a person who did any action at last. However, in the case of Search portlet result, the initials icon displays using thread owner's initials.

Steps to reproduce

1. Startup DXP
2. Sign In with "[e-mail]"
3. Add a user named "abc", and to be a member of a default site with Site Owner role
4. Add a MB thread titled "Test Thread" (owned by [e-mail])
5. Sign Out, and Sign In with "abc"
6. Go into "Test Thread", and Reply to Main Thread
7. Go back to Content > Message Boards
   Note that initials icon uses a name of a person who replied (abc)
8. Go to homepage
9. Search with "Thread" (Search portlet)

Expected Results
Both entries are shown with their respective posters' initials

Actual Results
Both entries are shown, however only the thread owner's initials are shown.

Reproduced in
DXP + FP11
ee-7.0.x (7d688430039d6af6cb1d6835d70a568a362150a8)
master (3a2001cab0f6785a243c9b1f709596c041173c85)