Migrate set-output to $GITHUB_OUTPUT

[tanakakc]

https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

[znz]

test failed, but I think it does not relate this change.

https://github.com/ruby/etc/actions/runs/3973339783/jobs/6812063033#step:1:36

Warning: Failed to download action 'https://api.github.com/repos/ruby/setup-ruby/tarball/93287a1fa82c6ddbb6d8db978df4b0119cd8879f'. Error: The request was canceled due to the configured HttpClient.Timeout of 100 seconds elapsing.
Warning: Back off 29.469 seconds before retry.
Warning: Failed to download action 'https://api.github.com/repos/ruby/setup-ruby/tarball/93287a1fa82c6ddbb6d8db978df4b0119cd8879f'. Error: The request was canceled due to the configured HttpClient.Timeout of 100 seconds elapsing.
Warning: Back off 10.37 seconds before retry.
Error: The request was canceled due to the configured HttpClient.Timeout of 100 seconds elapsing.