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• The jQuery.timeago version we have is outdated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)