Ability to cache GOBIN

[shoenig]

This action is great! Thanks for making it.

I was wondering if you'd be open to adding the ability to cache the $GOBIN path in addition to the modules paths.

We have some complex builds that go install about a dozen tools for things like code generation, linting, etc. some of which get re-used across jobs. If they're cached, the Go compiler can avoid recompiling them in each job.

[magnetikonline]

Thanks @shoenig for the kind words 👍.

I reckon if I did add that, it would need to be an optional parameter to the action - since I don't think everyone would want that as standard behaviour. I'll leave the card open and see if I can shoe-horn in this feature for you when time allows 😄.