Replace jQuery.timeago with timeago.js

What does this MR do?

Replaces jQuery.timeago with timeago.js

Are there points in the code the reviewer needs to double check?

• Check to make sure its working everywhere 😄
• Check to make sure the timeago wording matches what we have now (I think I've got this down but an extra pair of 👀 would help too)

Why was this MR needed?

• The jQuery.timeago version we have is outdated
• timeago.js is smaller (7.19 KB => 4.52 KB)
• timeago.js has no jQuery dependency
• removes all inline javascript ⚔ for timeago

Screenshots (if relevant)

None

Does this MR meet the acceptance criteria?

• CHANGELOG entry added
• Tests
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if you do - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Closes #21793 (closed)