The GitHub Actions set-output and save-state commands being used with stdout are insecure and were deprecated as of 11th October 2022 and will be disabled and start erroring on 1st June 2023. Action and workflow authors who are using save-state or set-output via stdout to use new environment variables provided.

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

Warnings about the commands being deprecated are showing up in logs like below:

Warning: The `set-output` command is deprecated and will be disabled soon. Please upgrade to using Environment Files. For more information see: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/