Timeline in exams page

[pedroafmonteiro]

Closes #1452

Review checklist

• Terms and conditions reflect the current change
• Contains enough appropriate tests
• If aimed at production, writes a new summary in whatsnew/whatsnew-pt-PT
• Properly adds an entry in changelog.md with the change
• If PR includes UI updates/additions, its description has screenshots
• Behavior is as expected
• Clean, well-structured code

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 66 lines in your changes missing coverage. Please review.

Project coverage is 11%. Comparing base (4ec1472) to head (ace7d8b).
Report is 1 commits behind head on ui/redesign.

❌ Your project check has failed because the head coverage (11%) is below the target coverage (70%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

@@             Coverage Diff             @@
##           ui/redesign   #1472   +/-   ##
===========================================
- Coverage           11%     11%   -0%     
===========================================
  Files              268     268           
  Lines             7660    7675   +15     
===========================================
  Hits               820     820           
- Misses            6840    6855   +15