Remove quick_retry feature

[tstone]

Background

This PR removes the "quick retry" feature of atomic_cache.

Why

Quick retry works best in situations where the cached value changes slowly but the time to re-generate a value is quick. These are unlikely to be situations where the overhead of atomic_cache would be seriously considered. Along these lines, there aren't currently any plans to use quick retry in a production setting at Ibotta, which is yet a further signal that this feature is adding unnecessary complication, and can be removed.

Versioning

This is a backwards-incompatible change to a pre-release gem. To avoid signalling a "production readiness" the version will increment from 0.3.0.rc1 to 0.4.0.rc1.

Tasks

• Code of Conduct reviewed
• Specs written and passing
• Backwards-incompatible changes called out in this PR
• Increment the version file (./lib/atomic_cache/version.rb) when applicable
  • See semver.org for what segment to increment

[lebeerman]

there aren't currently any plans to use quick retry in a production setting at Ibotta, which is yet a further signal that this feature is adding unnecessary complication, and can be removed.

Totally agree. Seems like last_known_value check is sufficient.