Switching from set-output to GITHUB_OUTPUT and reducing unnecessary runs

[tolzhabayev]

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

This PR is:

• switching to using the new format
• additionally reduces the amount of jobs running per open PR, as soon as something new is pushed the previous runs will be cancelled