ModuleAPI: overwrite_login action was not stopping the existing client resulting in the action failing with rust-sdk (#12272)

* Fix overwrite login action not stopping client

* remove unneeded fixture for overwrite login test

* Fix playwrite bad import of app sources

* revert uneeded change on fore OnLoggedIn causing side effects

* Add unit test for overwrite login action

* remove un needed ts-ignore

playwright/e2e/login/overwrite_login.spec.ts

@@ -0,0 +1,53 @@
+/*
+Copyright 2024 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { test, expect } from "../../element-web-test";
+import { logIntoElement } from "../crypto/utils";
+
+test.describe("Overwrite login action", () => {
+    test("Try replace existing login with new one", async ({ page, app, credentials, homeserver }) => {
+        await logIntoElement(page, homeserver, credentials);
+
+        const userMenu = await app.openUserMenu();
+        await expect(userMenu.getByText(credentials.userId)).toBeVisible();
+
+        const bobRegister = await homeserver.registerUser("BobOverwrite", "p@ssword1!", "BOB");
+
+        // just assert that it's a different user
+        expect(credentials.userId).not.toBe(bobRegister.userId);
+
+        const clientCredentials /* IMatrixClientCreds */ = {
+            homeserverUrl: homeserver.config.baseUrl,
+            ...bobRegister,
+        };
+
+        // Trigger the overwrite login action
+        await app.client.evaluate(async (cli, clientCredentials) => {
+            // @ts-ignore - raw access to the dispatcher to simulate the action
+            window.mxDispatcher.dispatch(
+                {
+                    action: "overwrite_login",
+                    credentials: clientCredentials,
+                },
+                true,
+            );
+        }, clientCredentials);
+
+        // It should be now another user!!
+        const newUserMenu = await app.openUserMenu();
+        await expect(newUserMenu.getByText(bobRegister.userId)).toBeVisible();
+    });
+});