Add the action policy inheritation schema

Summary:
Ref T2103
This change allows for actions to inherit policies from other actions. By default the "show" action inherits from the "list" action and vice-versa. The change also introduces a set of interface methods for this API to the Collection class; thanks to it, the inheritance schema can be modified at runtime.

Test Plan: Run the attached test suite

Reviewers: #reviewers, kuba-orlik

Reviewed By: #reviewers, kuba-orlik

Maniphest Tasks: T2103

Differential Revision: https://hub.sealcode.org/D960