Allow bypassing cache to make it compatible with runners that do not support it

[dacabdi]

I am currently using nektos/act to run GitHub Actions locally. The project is pretty cool but it does not support cache. A bunch of other actions support disabling the cache or proceeding even if it fails to get a hit. It would be good if we could do the same here and opt out of the cache feature when running in an environment that does not support it.

See nektos/act#989