Update Ubuntu release chart

[mtruj013]

Done

• Updated "end of support" dates for 18.04 and 20.04 as per sheet

QA

• View the site locally in your web browser at: https://ubuntu-com-14738.demos.haus/about/release-cycle#ubuntu
• See that the chart and table have been updated

Issue / Card

Fixes https://warthogs.atlassian.net/browse/WD-19280

Screenshots

[webteam-app]

Demo

Jenkins

demos.haus

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 72.32%. Comparing base (82d22bd) to head (02d1f93).
Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #14738   +/-   ##
=======================================
  Coverage   72.32%   72.32%           
=======================================
  Files         120      120           
  Lines        3404     3404           
  Branches     1174     1174           
=======================================
  Hits         2462     2462           
  Misses        917      917           
  Partials       25       25           

[fasih-mehmood]

LGTM, thanks!