Add a tag to skip caching for a task

[ZXCroon]

There are cases where I want to avoid caching a task. This happens if this task is just a "debug" task, which I don't want ansible-bender to spend a lot of time doing caching for the task. And we don't want to cache it also because I want it to be executed for every run for debugging purpose. Another example is "set_fact" or any kinds of tasks that register a variable. I want to avoid caching for these tasks, because if it is cached and skipped, the variable will not be set which is wrong.

Note that this is different than no-cache or stop-layering, which will stop caching for all following tasks.

I think the implementation is easy (at least from my experiment). Just add a tag like SKIP_CACHE_TAG=skip-cache. And in snapshoter.py, add

if SKIP_CACHE_TAG in getattr(task, "tags", []):
    return

into both _maybe_load_from_cache and _snapshot functions. I can also create the MR. Just want to make sure you are ok with this enhancement

[TomasTomecek]

Thank you for your time submitting this request!

If what you imply is skipping caching of one task and continue further with the caching process: I don't think this is a good idea because one could get inconsistent results easily or even weird errors which won't make sense.

On the other hand, I understand the request and would accept such a pull request with a big fat disclaimer in the docs about the consequences of this behaviour :)