ActiveSupport::Cache::MonetaStore: Rails 6 support - Implement/advertise cache versioning support

[jimcavoli]

Introduced by rails/rails#33932 for Rails 6, without implementing a .supports_cache_versioning? on ActiveSupport::Cache::MonetaStore, the application will raise an exception encouraging the user to change adapters entirely or alternatively disable recyclable cache keys (see rails/rails#29092).

The only notable change is that the passed ActiveSupport::Cache::Entry includes a version attribute (readable) that contains the version part of the cache key so that cache keys remain the same for particular entries.

[asppsa]

Thanks for bringing this to my attention - I had no idea this had been added to Rails!

[asppsa]

I think this basically boils down to being able to store version metadata in the cache, and to check that version against a supplied one when fetching. This may mean it's possible to implement on top of #107.