Use act from @test-utils in SC (#32432)

* test: use `act` from `@test-utils` in SC

* chore: add rules to enforce use of act from `@test-utils`

packages/shared-components/.eslintrc.cjs

@@ -30,6 +30,18 @@ module.exports = {
         "react/jsx-key": ["error"],
         "matrix-org/require-copyright-header": "error",
         "react-compiler/react-compiler": "error",
+        "no-restricted-imports": [
+            "error",
+            {
+                paths: [
+                    {
+                        name: "react",
+                        importNames: ["act"],
+                        message: "Please use @test-utils instead.",
+                    },
+                ],
+            },
+        ],
     },
     overrides: [
         {

packages/shared-components/src/room-list/RoomListPrimaryFilters/RoomListPrimaryFilters.test.tsx

@@ -5,8 +5,8 @@
  * Please see LICENSE files in the repository root for full details.
  */
 
-import React, { act } from "react";
+import React from "react";
-import { render, screen } from "@test-utils";
+import { act, render, screen } from "@test-utils";
 import userEvent from "@testing-library/user-event";
 import { composeStories } from "@storybook/react-vite";
 import { describe, it, expect, vi, beforeEach } from "vitest";