Fix for deprecated of set-output in GH actions

[fredericsimard]

GitHub has deprecated set-output and will eventually make it unusable, so this is a preventative fix. See more info here: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

[github-actions]

✅ Rule acceptance tests passed.
New Errors: 0 out of 1470 datasets (~0%) are invalid due to code change, which is less than the provided threshold of 1%.
Dropped Errors: 0 out of 1470 datasets (~0%) are invalid due to code change, which is less than the provided threshold of 1%.
New Warnings: 0 out of 1470 datasets (~0%) are invalid due to code change, which is less than the provided threshold of 1%.
Dropped Warnings: 0 out of 1470 datasets (~0%) are invalid due to code change, which is less than the provided threshold of 1%.
0 out of 1470 sources (~0 %) are corrupted.
Commit: c134676
Download the full acceptance test report here (report will disappear after 90 days).
✅ Rule acceptance tests passed.