Ps/improve state provider fakers (#7494)

* Expand state provider fakes

- default null initial value for fake states
- Easier mocking of key definitions through just the use of key names
  - allows for not exporting KeyDefinition as long as the key doesn't collide
- mock of fake state provider to verify `get` calls
- `nextMock` for use of the fn mock matchers on emissions of `state$`
- `FakeAccountService` which allows for easy initialization and working with account switching

* Small bug fix for cache key collision on key definitions unique by only storage location

* Fix initial value for test

libs/common/src/auth/services/account.service.spec.ts

@@ -36,8 +36,6 @@ describe("accountService", () => {
     sut = new AccountServiceImplementation(messagingService, logService, globalStateProvider);
 
     accountsState = globalStateProvider.getFake(ACCOUNT_ACCOUNTS);
-    // initialize to empty
-    accountsState.stateSubject.next({});
     activeAccountIdState = globalStateProvider.getFake(ACCOUNT_ACTIVE_ACCOUNT_ID);
   });
 
@@ -57,7 +55,10 @@ describe("accountService", () => {
       accountsState.stateSubject.next({ [userId]: userInfo(AuthenticationStatus.Unlocked) });
       activeAccountIdState.stateSubject.next(userId);
 
-      expect(emissions).toEqual([{ id: userId, ...userInfo(AuthenticationStatus.Unlocked) }]);
+      expect(emissions).toEqual([
+        undefined, // initial value
+        { id: userId, ...userInfo(AuthenticationStatus.Unlocked) },
+      ]);
     });
 
     it("should update the status if the account status changes", async () => {