investigate: can we merge sequence-based caches with request-based caches?

[domanchi]

We perform sequence-based caching within the Response object (source). However, this doesn't support request-based caches, which are needed to have consistent values within dependent factory fixtures.

Currently, we handle this with an explicit call to clear_cache after the request is completed. However, this is kinda ugly and potentially foot-gun-like. Can we do better?

Full context here: https://github.com/Yelp/fuzz-lightyear/pull/14#discussion_r324943275