Update actions versions and output method

[rffontenelle]

Updates actions/checkout@v4 to the latest major version to drop deprecated nodejs version, and replace deprecated ::set-output method with the current method.

This solves the warnings:

The following actions uses node12 which is deprecated and will be forced to run on node16: actions/checkout@v2. For more info: https://github.blog/changelog/2023-06-13-github-actions-all-actions-will-run-on-node16-instead-of-node12-by-default/

and

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/

[inknos]

ah this was on my backlog for a long time! thanks