fix: disable caching of non-static entities

[bitpshr]

This pull request removes caching from non-static endpoints. This was a total oversight and could result in stale, cached entities being returned instead of the most up-to-date version.

After this change, the entity types below are the only ones that we'll cache (since they are all either static or requested using a static sha):

Activity
Asset
Changeset
Commit
Data
File
Layer
Membership
Notification
Preview
Share

References https://goabstract.atlassian.net/browse/PLATFORM-490

[amccloud]

Good catch! Might be possible to introduce a new strategy for caching these in the future with updatedAt and overall staleness

[bitpshr]

@amccloud agreed; we could couple that with the ability to explicitly disable caching during a request by adding an option that all cached endpoints support for max-portability.