CI: Remove usage of ubuntu-20.04

[felixfontein]

SUMMARY

ubuntu20.04 will get removed eventually.

Ref: https://forum.ansible.com/t/40187

ISSUE TYPE

• Test Pull Request

COMPONENT NAME

CI

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (f99d8a9) to head (6571bfe).
Report is 1 commits behind head on stable-1.

Additional details and impacted files

@@            Coverage Diff             @@
##           stable-1       #25   +/-   ##
==========================================
  Coverage    100.00%   100.00%           
==========================================
  Files             3         3           
  Lines            90        90           
  Branches         23        23           
==========================================
  Hits             90        90           

Flag	Coverage Δ
sanity	25.92% <ø> (ø)
units	100.00% <ø> (ø)

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