[lib] refactor logout action in UserStore to ops

Summary:
Convert logic for ops approach.

Depends on D9801

Test Plan: Logout

Reviewers: tomek

Reviewed By: tomek

Subscribers: ashoat, wyilio

Differential Revision: https://phab.comm.dev/D9802

lib/reducers/user-reducer.js

@@ -211,6 +211,16 @@ function reduceUserInfos(
     (action.type === setNewSessionActionType &&
       action.payload.sessionChange.cookieInvalidated)
   ) {
+    const processedUserInfos: UserInfos = processUserStoreOps(state.userInfos, [
+      { type: 'remove_all_users' },
+    ]);
+    assertUserStoresAreEqual(
+      processedUserInfos,
+      {},
+      action.type,
+      onStateDifference,
+    );
+
     if (Object.keys(state.userInfos).length === 0) {
       return [state, []];
     }