Extend createServicePolicy to support live network status

In a future commit we will introduce changes to `network-controller` so
that it will keep track of the status of each network as requests are
made. These updates to `createServicePolicy` assist with that.

See the changelog for a list of changes to the `ServicePolicy` API.

Besides the changes listed there, the tests for `createServicePolicy`
have been refactored slightly so that it is easier to maintain in the
future.

Author: mcmire

packages/controller-utils/CHANGELOG.md

@@ -7,6 +7,19 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Add `getCircuitState` method to `ServicePolicy` ([#7164](https://github.com/MetaMask/core/pull/7164))
+  - This can be used when working with a chain of services to know whether a service's underlying circuit is open or closed.
+- Add `getLastInnerFailureReason` method to `ServicePolicy` ([#7164](https://github.com/MetaMask/core/pull/7164))
+  - This can be used when working with a chain of services to obtain the last error that the circuit breaker policy captured after executing the service.
+- Add `onAvailable` method to `ServicePolicy` ([#7164](https://github.com/MetaMask/core/pull/7164))
+  - This can be used to listen for the initial successful execution of the service, or the first successful execution after the service becomes degraded or the circuit breaks.
+- Add `reset` method to `ServicePolicy` ([#7164](https://github.com/MetaMask/core/pull/7164))
+  - This can be used when working with a chain of services to reset the state of the circuit breaker policy (e.g. if a primary recovers and we want to reset the failovers).
+- Export `CockatielEventEmitter` and `CockatielFailureReason` from Cockatiel ([#7164](https://github.com/MetaMask/core/pull/7164))
+  - These can be used to further transform types for event emitters/listeners.
+
 ## [11.15.0]
 
 ### Added