Updates Timeline Documentation

[FutzMonitor]

📑 Summary

My PR makes some small changes to the timeline documentation, such as:

1. Updates the Wikipedia citation to include a link.
2. Removed periods from documentation sections to be consistent (some had periods, some didn't).
3. Added a space to a coding example for spacing consistency.

Resolves [This PR does not resolve any issues].

📏 Design Decisions

My implementation simply changes some text inside of docs/syntax/timeline.md so that there's some more consistency and helpful links for Mermaid users.

📋 Tasks

Make sure you

• 📖 have read the contribution guidelines
• 💻 have added necessary unit/e2e tests.
• 📓 have added documentation. Make sure MERMAID_RELEASE_VERSION is used for all new features.
• 🔖 targeted develop branch

[netlify]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 43.20%. Comparing base (4e12157) to head (39d870d).
Report is 3 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff              @@
##           develop    #5315       +/-   ##
============================================
- Coverage    76.40%   43.20%   -33.21%     
============================================
  Files          175       23      -152     
  Lines        14514     5115     -9399     
  Branches       866       23      -843     
============================================
- Hits         11090     2210     -8880     
+ Misses        3212     2904      -308     
+ Partials       212        1      -211     

Flag	Coverage Δ
e2e	?
unit	43.20% <ø> (ø)

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