[REFACTOR] Extract fetch_latest_revision generic function for cache
[REFACTOR] Extract fetch_latest_revision generic function for cache

This will allow us to fetch any type of key generically.

Signed-off-by: Christopher Maier <b4598f17a90ef80817bae8ad6c37249740caafb4@chef.io>

habitat-sh/habitat,habitat-sh/habitat,habitat-sh/habitat,habitat-sh/habitat,habitat-sh/habitat,habitat-sh/habitat,habitat-sh/habitat,habitat-sh/habitat