Update workflow jobs for release artifacts

[fktn-k]

This PR updates existing GitHub Actions workflow jobs for release artifacts.
From the next release on, new tar.gz & zip archives are to be also published.
They contain only minimum required files (roughly the top CMakeLists.txt & include/single_include directories) to be used as a CMake project since this repository now contains many files which are not needed by a client app which just uses fkYAML.

See the workflow result for actual contents of release artifacts.

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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.