Update GitHub Actions workflow jobs using macOS related runner images

[fktn-k]

Due to the support policy changes as described in the issue actions/runner-images#10703, Xcode versions to use in GitHub Actions workflow jobs have been updated.
Now, those jobs uses

• Xcode 15.x versions with the macos-14 runner image and
• Xcode 16.x versions with the macos-15 runner image.

Furthermore, since the macos-12 runner image will be removed on 12/3/24 as described in the issue actions/runner-images#10721, workflow jobs using the runner image have been removed, and therefore

• Xcode 13.x versions are no longer tested but
• Xcode 14.x versions are still tested using the macos-13 runner image.

The supported compilers list has also been updated according to the above changes.

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Pull Request Checklist

Read the CONTRIBUTING.md file for detailed information.

• Changes are described in the pull request or in a referenced issue.
• The test suite compiles and runs without any error.
• The code coverage on your branch is 100%.
• The documentation is updated if you added/changed a feature.

Please don't

• The C++11 support varies between different compilers and versions. Please note the list of supported compilers. Some compilers like GCC 4.7 (and earlier), Clang 3.3 (and earlier), or Microsoft Visual Studio 13.0 and earlier are known not to work due to missing or incomplete C++11 support. Please refrain from proposing changes that work around these compiler's limitations with #ifdefs or other means.
• Please refrain from proposing changes that would break YAML specifications. If you propose a conformant extension of YAML to be supported by the library, please motivate this extension.
• Please do not open pull requests that address multiple issues.