The `set-output` command is deprecated and will be disabled soon.

[tjoyal]

This warning was fixed in #231. It is not present in the latest release which is v0.3.0.

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

Starting 1st June 2023 workflows using save-state or set-output commands via stdout will fail with an error.

Would we consider a version bump due to the importance of said change?

Alternatively for those looking for a quick way out: uses: actions/add-to-project@51e172a520b4925f1909cbd44f0e991607db88a9

[mattcosta7]

We've released v0.4.0 which contains the updates from that sha!