Remove feature_many_integration_managers

Rationale: If we want this feature, design will do it properly.

src/dispatcher/actions.ts

@@ -278,12 +278,6 @@ export enum Action {
      */
     OpenReportEventDialog = "open_report_event_dialog",
 
-    /**
-     * Fired when the tabbed integration manager dialog needs to be opened.
-     * Payload: OpenTabbedIntegrationManagerDialogPayload
-     */
-    OpenTabbedIntegrationManagerDialog = "open_tabbed_imanager_dialog",
-
     /**
      * Fired when something within the application has determined that a logout,
      * or logout-like behaviour, needs to happen. Specifically meant to target

src/dispatcher/payloads/OpenTabbedIntegrationManagerDialogPayload.ts

@@ -1,29 +0,0 @@
-/*
-Copyright 2022 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 { Room } from "matrix-js-sdk/src/models/room";
-import { Optional } from "matrix-events-sdk";
-
-import { ActionPayload } from "../payloads";
-import { Action } from "../actions";
-
-export interface OpenTabbedIntegrationManagerDialogPayload extends ActionPayload {
-    action: Action.OpenTabbedIntegrationManagerDialog;
-
-    room: Optional<Room>;
-    screen: Optional<string>;
-    integrationId: Optional<string>;
-}