docs(readme): remove macos-12 from readme

[ReenigneArcher]

Description

macos-12 runners are deprecated and will soon be removed.

Screenshot

Issues Fixed or Closed

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Dependency update (updates to dependencies)
• Documentation update (changes to documentation)
• Repository update (changes to repository files, e.g. .github/...)

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated the in code docstring/documentation-blocks for new or existing methods/components

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.75%. Comparing base (4b35311) to head (370f3e5).
Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #104   +/-   ##
=======================================
  Coverage   92.75%   92.75%           
=======================================
  Files           1        1           
  Lines         138      138           
=======================================
  Hits          128      128           
  Misses         10       10           

Flag	Coverage Δ
Linux	92.75% <ø> (ø)
macOS	92.75% <ø> (ø)

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