Update CI badges in README

[iche033]

🦟 Bug fix

Summary

focal -> jammy
ign -> gz

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (2759bff) 70.08% compared to head (dc2945f) 70.08%.

Additional details and impacted files

@@           Coverage Diff            @@
##           gz-gui8     #603   +/-   ##
========================================
  Coverage    70.08%   70.08%           
========================================
  Files           39       39           
  Lines         5362     5362           
========================================
  Hits          3758     3758           
  Misses        1604     1604           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.