[feat req] Defer file accumulation to cleanup phase (post action)

[mk-pmb]

What would you like to be added?

I'd like a flag to defer the file accumulation and upload to the cleanup phase, after the CI run (and potentially failed).

Why is this needed?

Composite actions currently don't support cleanup steps. While not a general solution, such a "just schedule for later" flag in upload-artifact would at least solve my current problem today:

My composite action prepares stuff in the repo. One feature is to create a logs directory at a default location. I'd like to add a post step that packs that logs dir as an artifact.